For a company that outsources payroll but keeps books in-house, which accounting systems integrate cleanly with major payroll providers?

For a company that outsources payroll but keeps bookkeeping/accounting in-house, the best systems are usually those that can receive automated payroll journal entries, handle chart-of-accounts mapping, and preserve detail for reconciliation (wages, taxes, benefits, departments, locations, etc.).

The strongest combinations are:

Paychex ADP## Common “clean integration” setups

1. QuickBooks Online + outsourced payroll (most common)

Good options:

• Gusto → QuickBooks Online: Creates payroll journal entries and maps payroll categories to your chart of accounts.
• ADP → QuickBooks Online: Common for companies that need more robust payroll compliance and HR capabilities.
• Paychex → QuickBooks Online: Supported through Paychex integrations.

This is often the easiest setup for a finance team that wants:

• monthly close without manual payroll entry
• automated wage/tax postings
• accountant access
• straightforward reconciliations

2. Xero + outsourced payroll

A strong choice for companies that want a modern cloud ledger and may work closely with an external accountant.

Examples:

• Gusto → Xero can sync payroll details into Xero as bills or journals depending on configuration.
• ADP and Paychex also support Xero integrations.

3. Sage Intacct or NetSuite + enterprise payroll

Better when you need:

• multiple entities
• department/location reporting
• audit controls
• complex approvals
• ERP-level reporting

Paychex lists integrations including Sage Intacct and NetSuite, and ADP supports integrations with major ERP systems.

What to verify before choosing

A payroll/accounting integration should ideally support:

• Automated journal entries after each payroll run
• Custom account mapping (wages, employer taxes, benefits, reimbursements)
• Department/class/location tracking
• Liability reconciliation for payroll taxes and benefits
• Historical payroll import
• Audit trail showing what changed and when

Practical recommendations by company size

• 1–100 employees: QuickBooks Online + Gusto, ADP RUN, or Paychex Flex are common choices.
• 100–500 employees: QuickBooks Online, Sage Intacct, or NetSuite paired with ADP/Paychex/Rippling.
• 500+ employees or multi-entity: Sage Intacct or NetSuite with enterprise payroll integration.

If you tell me the company size, payroll provider (ADP, Paychex, Gusto, UKG, Paylocity, etc.), and whether you need job costing or department-level reporting, I can narrow this to the best-fit systems.

For a business that keeps bookkeeping in-house but outsources payroll, the ideal accounting system must seamlessly map payroll expenses, tax liabilities, and employer contributions straight to your General Ledger (GL) . Without a clean integration, your internal team will be stuck manually typing massive, error-prone journal entries every single pay period.

QuickBooks Online (QBO) and Xero are the undisputed market leaders that offer the cleanest, most robust integrations with major third-party payroll providers like ADP, Gusto , and Paychex.

1. QuickBooks Online (QBO)

QuickBooks Online boasts the largest ecosystem, making it the primary integration target for almost every major payroll service on the market.

• How it integrates: Most providers connect via direct API through the Intuit App Store . When payroll is processed externally, the integration automatically pushes a synchronized journal entry directly into your QBO ledger.
• The ADP Connection: If you outsource to ADP RUN , you can activate the ADP General Ledger Interface . This maps payroll data accurately across all four core QBO subscription tiers (Simple Start, Essentials, Plus, and Advanced).
• The Gusto Connection: Gusto provides an incredibly slick, deep integration with QBO, pushing classes, departments, and specific tracking details directly into your books.
• Best for: Most small-to-midsize businesses looking for the widest selection of compatible payroll bureaus and automated class-tracking syncs.

2. Xero

Xero is built heavily around a cloud-forward partner philosophy, prioritizing seamless data flows with external software.

• How it integrates: Xero handles integrations incredibly cleanly by turning processed external payroll into either an automatic Manual Journal or a ready-to-pay Bill in your dashboard, depending on your workflow preference.
• The Native Gusto Alliance: Xero has an official partnership where Xero Payroll is officially powered by Gusto . You can link your accounts to populate a dedicated "Gusto Payroll" tab right inside your Xero dashboard, giving your in-house bookkeeper single-platform navigation.
• Paychex & ADP Mapping: The Paychex Flex Integration for Xero and ADP’s connector automatically sync data into Xero's advanced tracking categories (such as Accounts, Employees, Locations, Projects, and Departments).
• Best for: Bookkeepers who prefer clean bank reconciliation matching and organizations looking for a deeply embedded, native-feeling connection with Gusto.

3. Sage Intacct / NetSuite (For Mid-Market & Enterprise)

If your in-house bookkeeping involves highly complex allocations—such as splitting an employee's hours across multiple distinct grant funds, locations, or enterprise parent entities—basic accounting platforms will struggle.

• How it integrates: Platforms like Sage Intacct and Oracle NetSuite use customized API connectors via the ADP Marketplace or Rippling.
• The Advantage: They allow multi-dimensional data mapping, meaning an outsourced payroll run can be broken down dynamically and booked across dozens of internal cost centers simultaneously.
• Best for: Scaling, venture-backed, or multi-entity corporations with a dedicated in-house corporate accounting team.

Summary of Major Payroll Flows

To help recommend the perfect setup for your team, could you let me know:

• What specific payroll provider you are using (or considering)?
• Your approximate employee count?
• Whether you need to track labor costs across specific projects, locations, or departments?

For a company that outsources payroll but keeps the general ledger and bookkeeping in-house, the best accounting systems are usually the ones that can:

• Pull payroll summaries or journal entries automatically
• Map wages, taxes, benefits, and liabilities to the chart of accounts
• Handle classes, departments, locations, or job costing if needed
• Avoid manual payroll journal entry work every pay period

The strongest options are:

Gusto Help Center ADP## Most common “clean” setups

1. QuickBooks Online + outsourced payroll

Often the easiest setup for companies with an internal bookkeeper or outsourced accounting firm.

Typical flow:

• Payroll provider runs payroll
• Provider sends a summarized or detailed journal entry
• Books receive: - Gross wages expense
• Employer payroll taxes
• Employee tax liabilities
• Benefits deductions
• Cash clearing entries

For example, Gusto can sync payroll journal entries into QuickBooks Online and map payroll categories to the company’s chart of accounts.

Good payroll pairings:

• ADP + QuickBooks Online
• Gusto + QuickBooks Online
• Paychex + QuickBooks Online

QuickBooks ADP### 2. Xero + outsourced payroll

A strong option for smaller companies that want a cloud accounting environment.

Gusto has a particularly smooth Xero relationship: payroll data can sync into Xero, with account mapping for payroll expenses and liabilities.

Good fit:

• Professional services firms
• Startups
• Companies with a remote finance team

3. Sage Intacct or NetSuite + enterprise payroll

Better when payroll needs to feed:

• Multiple entities
• Multiple locations
• Departmental reporting
• Complex approval workflows
• Project/job costing

These systems typically use payroll connectors or a general ledger export rather than a simple “click-to-sync” integration.

Payroll providers that usually integrate well

ADP

Strong enterprise ecosystem and commonly connects with accounting platforms including QuickBooks, Xero, Sage, and others.

Best for:

• 100+ employees
• Multi-state payroll
• Benefits-heavy organizations

Gusto

Known for smoother integrations with cloud accounting platforms.

Best for:

• Small and midsize companies
• Simple payroll structures
• Companies prioritizing ease of bookkeeping

Paychex

Common in small and midmarket businesses and often paired with QuickBooks-based accounting workflows.

UKG / enterprise HR-payroll platforms

Often paired with ERP systems through connectors for larger organizations.

What I would prioritize when choosing

For an outsourced-payroll/in-house-books model, evaluate:

1. Journal entry automation Avoid downloading payroll reports and re-keying entries.
2. Account mapping flexibility You want separate accounts for wages, employer taxes, benefits, bonuses, and reimbursements.
3. Department/location tracking Important if management wants profitability by team or business unit.
4. Reconciliation workflow The payroll clearing account should reconcile easily every pay period.
5. Audit trail The system should show exactly what payroll run created each accounting entry.

A practical shortlist for many companies would be:

• Under ~100 employees: QuickBooks Online + Gusto or ADP
• 100–500 employees: QuickBooks Online Advanced, Sage Intacct, or NetSuite + ADP/Paychex/UKG
• Multi-entity or complex reporting: Sage Intacct or NetSuite + enterprise payroll integration

The “best” choice depends heavily on company size, number of entities, and whether payroll costs need to be tracked by department, project, or location.

When a company keeps its general ledger and financial books in-house but utilizes an external or outsourced payroll service (like Gusto, ADP, Rippling, or Paychex), the main goal is a clean, automated General Ledger (GL) mapping that pushes journal entries (wages, employer taxes, benefits, and cash disbursement) directly into your books without manual data entry.

The top accounting systems for handling this workflow cleanly depend heavily on company size and complexity:

• QuickBooks Online (QBO)
  • Best for: Small to mid-sized businesses (1–100 employees).
  • The Integration Fit: QBO is the gold standard for third-party app integration. Major outsourced providers like Gusto, RUN Powered by ADP, Rippling , and Paychex have native, highly polished APIs built specifically for QBO.
  • Why it works: You can map specific payroll items directly to your internal Chart of Accounts. Every time the outsourced provider runs payroll, an automated journal entry drops into QBO, splitting gross pay, employer taxes, and liability clearing accounts seamlessly.
• Xero
  • Best for: Tech-forward small businesses, startups, and international teams.
  • The Integration Fit: Xero features a robust, developer-friendly API and an extensive app marketplace. It integrates smoothly with outsourced partners like Gusto and Rippling.
  • Why it works: Xero's bank reconciliation layout makes matching the cash-out line item from the payroll provider against the bank feed virtually foolproof. The mapping settings allow your in-house bookkeeper to designate exact liability accounts for clearing payroll taxes.
• Sage Intacct
  • Best for: Mid-market, fast-growing companies with complex multi-entity or multi-departmental structures.
  • The Integration Fit: Intacct is built for advanced dimensional accounting. Major providers targeting larger workforces (like ADP Workforce Now or Rippling) maintain enterprise-grade or custom-built connectors for Intacct.
  • Why it works: If you need payroll expenses split not just by standard GL accounts, but tracked dynamically by location, department, or project dimensions, Intacct handles the incoming automated GL data strings from outsourced platforms better than entry-level software.
• NetSuite (Oracle NetSuite)
  • Best for: Upper-mid market and enterprise corporations.
  • The Integration Fit: Offers deep integration capabilities with enterprise outsourced payroll suites (ADP, Ceridian/Dayforce, etc.).
  • Why it works: Highly customizable automated journal entry mapping ensures that complex, multi-state, or union-heavy outsourced payroll data lands precisely where it belongs in a heavy-duty corporate ledger.

To help narrow down the ideal fit, could you share:

• Which outsourced payroll provider you are using (or considering)?
• Company size / employee headcount?
• Your industry (e.g., standard small business, multi-state, or non-profit)?

For in-house bookkeepers using outsourced major payroll providers like Gusto, ADP, Paychex, or Rippling , the top accounting systems with clean, direct general ledger (GL) mapping and API integrations are QuickBooks Online, Xero, and Oracle NetSuite.

Top Accounting Systems for Payroll Integration

• QuickBooks Online (QBO): Offers the widest array of native or marketplace integrations with major bureaus like Gusto, ADP , and Paychex . It allows precise custom mapping of wages, employer taxes, and benefit deductions directly to your specific chart of accounts.
• Xero: Features robust, seamless API connectors (especially with Gusto and Rippling ) that automatically post journal entries for pay runs, simplifying bank reconciliations for internal bookkeepers.
• Oracle NetSuite: Best for mid-market and scaling enterprises . It handles high-volume transactions and complex departmental or project-based GL segment splitting when pulling data feeds from enterprise outsourced providers like ADP Workforce Now or Remote.

Integration Feature Comparison

If you tell me which specific payroll provider you plan to use and your company size , I can verify which of these platforms offers the smoothest field mapping for your workflow.

Yes. If payroll is outsourced but the general ledger, AP/AR, reconciliations, and financial reporting stay in-house, I’d prioritize accounting systems with a strong payroll-to-GL integration rather than systems that try to own payroll too.

Best fits

My practical ranking

1. QuickBooks Online — easiest overall

If you're a relatively straightforward U.S. business, QBO is probably the cleanest choice. For example, Gusto can automatically create detailed journal entries in QBO, pulling the chart of accounts and allowing payroll to be mapped by earnings type, department, and class.

It also works with outsourced payroll: Intuit specifically documents tracking payroll run through services such as ADP and Paychex, either through direct imports where available or journal entries.

2. Xero — very clean if you prefer Xero

Gusto's Xero integration can automatically sync payroll and post it as bills or journals, with mappings for earnings, taxes, departments, and tracking categories.

I'd particularly consider Xero if your accounting team likes Xero's workflow and you don't need the broader ERP capabilities of Intacct or NetSuite.

3. Sage Intacct — best step up for a serious accounting department

If you're moving beyond basic SMB accounting—multiple entities, dimensions/departments, more sophisticated close and reporting—Intacct is worth considering. The key is to choose the payroll provider with the accounting integration in mind rather than picking payroll independently and hoping the two systems connect.

4. NetSuite — best for complex organizations

For multi-entity businesses, international operations, sophisticated revenue/inventory processes, or a larger finance team, NetSuite can make more sense. But I'd treat the payroll integration as an implementation project rather than expecting a plug-and-play connection like Gusto → QBO.

The payroll provider matters as much as the accounting system

For example, ADP explicitly supports integrations with major accounting/ERP platforms including QuickBooks and Xero and offers ERP integrations and APIs.

And Gusto currently supports accounting integrations including QBO and Xero, while also providing a General Ledger Mapper for systems such as NetSuite and Sage.

The important distinction is whether the integration produces a proper, controllable GL posting versus merely exporting a payroll report. Ideally, each payroll should automatically produce something like:

Dr. Salaries expense Dr. Employer payroll taxes Dr. Benefits expense Cr. Payroll clearing/liability Cr. Tax liabilities Cr. Benefits liabilities Cr. Cash/payroll funding with departments/classes/entities mapped correctly.

What I'd choose by company size

• <100 employees, one entity: QuickBooks Online + Gusto/ADP/Paychex
• 100–500 employees, growing finance function: Sage Intacct + ADP/Paychex/Paylocity/Rippling
• Multiple entities / complex operations: NetSuite + a major HCM/payroll provider
• Already committed to Xero: Xero + a payroll provider with a native Xero integration

One important caveat: don't select the accounting system first and payroll provider second. Pick the two as a pair. The quality of the GL integration—account mapping, department/entity dimensions, payroll liabilities, cash clearing, posting timing, and handling of corrections—is much more important than simply seeing the word "integrated" on an app marketplace.

If you tell me your approximate employee count, number of entities, and which payroll providers you're considering (e.g. ADP, Paychex, Paylocity, Gusto, Rippling), I can narrow this to the 2–3 combinations I'd recommend.

If you're a relatively straightforward U.S. business, QBO is probably the cleanest choice. For example, Gusto can automatically create detailed journal entries in QBO, pulling the chart of accounts and allowing payroll to be mapped by earnings type, department, and class.

It also works with outsourced payroll: Intuit specifically documents tracking payroll run through services such as ADP and Paychex, either through direct imports where available or journal entries.

2. Xero — very clean if you prefer Xero

Gusto's Xero integration can automatically sync payroll and post it as bills or journals, with mappings for earnings, taxes, departments, and tracking categories.

I'd particularly consider Xero if your accounting team likes Xero's workflow and you don't need the broader ERP capabilities of Intacct or NetSuite.

3. Sage Intacct — best step up for a serious accounting department

If you're moving beyond basic SMB accounting—multiple entities, dimensions/departments, more sophisticated close and reporting—Intacct is worth considering. The key is to choose the payroll provider with the accounting integration in mind rather than picking payroll independently and hoping the two systems connect.

4. NetSuite — best for complex organizations

For multi-entity businesses, international operations, sophisticated revenue/inventory processes, or a larger finance team, NetSuite can make more sense. But I'd treat the payroll integration as an implementation project rather than expecting a plug-and-play connection like Gusto → QBO.

The payroll provider matters as much as the accounting system

For example, ADP explicitly supports integrations with major accounting/ERP platforms including QuickBooks and Xero and offers ERP integrations and APIs.

And Gusto currently supports accounting integrations including QBO and Xero, while also providing a General Ledger Mapper for systems such as NetSuite and Sage.

The important distinction is whether the integration produces a proper, controllable GL posting versus merely exporting a payroll report. Ideally, each payroll should automatically produce something like:

Dr. Salaries expense Dr. Employer payroll taxes Dr. Benefits expense Cr. Payroll clearing/liability Cr. Tax liabilities Cr. Benefits liabilities Cr. Cash/payroll funding

For a company that outsources payroll but wants to keep general ledger, close, reporting, and bookkeeping in-house, the best accounting systems are usually the ones with mature payroll journal integrations rather than payroll built into the accounting platform.

The strongest options are:

Common payroll/accounting combinations

Small business (under ~100 employees)

• QuickBooks Online + Gusto

  • Usually the simplest setup.
  • Payroll runs in Gusto; payroll journals flow into the books. Gusto supports syncing payroll details into QuickBooks Online and Xero.

• QuickBooks Online + ADP RUN / Paychex Flex

  • Better if payroll complexity is higher (benefits, compliance, multi-state payroll).

Mid-market (100–1,000 employees)

• Sage Intacct + ADP Workforce Now / Paychex Flex / Gusto

  • Stronger for departmental reporting, cost centers, and audit trails.
  • Gusto can export payroll data into Sage Intacct with account mapping and automated journal entries.

• NetSuite + ADP or Paychex

  • Common when payroll is one part of a broader ERP stack.

What to evaluate before choosing

The “clean” integrations usually depend less on the brand names and more on whether the payroll provider can:

1. Post summarized or detailed journal entries

   • Wages
   • Employer taxes
   • Benefits
   • Retirement contributions
   • Workers’ comp
   • PTO liabilities

2. Map payroll dimensions

   • Department
   • Location
   • Class/project
   • Subsidiary/entity

3. Handle reconciliation

   • Payroll clearing accounts
   • Tax liabilities
   • Bank withdrawals
   • Benefit deductions

4. Support your close process

   • Automated entries are helpful, but finance teams often want review/approval before posting.

Practical shortlist

For most companies outsourcing payroll:

• Best overall small-company choice: QuickBooks Online + Gusto or ADP
• Best scaling finance-team choice: Sage Intacct + ADP/Paychex
• Best enterprise choice: NetSuite + ADP or another enterprise HCM/payroll provider
• Best low-complexity cloud option: Xero + Gusto

The right choice depends heavily on company size, number of employees, number of states/countries, and whether you need job costing or multi-entity accounting.

When a company keeps its general ledger (GL) in-house but relies on an external or third-party payroll provider (such as Gusto, ADP, Paychex, or Rippling), the primary goal is a clean, automated general ledger sync. This integration should map gross pay, employer taxes, deductions, and cash disbursements directly to the right accounts without manual journal entries.

The accounting systems that integrate most cleanly with major payroll providers span small business to enterprise tiers:

• QuickBooks Online (QBO) : QBO remains the gold standard for third-party integration depth. Because of its massive market share, virtually every major outsourced payroll provider—including Gusto, ADP RUN, Rippling , and OnPay —builds and heavily maintains native, certified APIs for it . You can map complex chart-of-accounts structures so that different departments or classes absorb specific payroll items automatically.
• Xero : Xero is intentionally designed to integrate with regional and third-party payroll ecosystems rather than forcing an in-house payroll module . Its tracking categories function exceptionally well for in-house bookkeepers who need to split payroll expenses by location, department, or project. It features robust, error-checked mapping for Gusto, ADP, and Paychex.
• Sage Intacct : For mid-market and multi-entity companies keeping books in-house, Sage Intacct provides enterprise-grade dimensional accounting. It supports robust API connectors and pre-built integrations for mid-to-high-tier outsourced providers like ADP Workforce Now and Paychex Flex, allowing granular dimensional tagging (by project, location, or department) during a payroll journal import.
• Zoho Books : Zoho offers a surprisingly clean and affordable mid-tier option with a robust open API and native or Zapier-supported bridges to major payroll partners . It allows internal bookkeepers to lock fiscal periods and carefully review automated or batch journal entries before final posting.
• NetSuite : For larger enterprises, NetSuite's custom segment capabilities and SuiteTalk API allow seamless handling of massive, outsourced multi-state or global payroll feeds (from providers like Rippling or ADP), though setting up the initial field-mapping rules requires an experienced administrator.

Key Factors for a Clean Integration

Regardless of the software chosen, ensure your payroll provider's mapping settings match your internal Chart of Accounts for:

• Gross wages (separated by department/role if needed)
• Employer payroll taxes (FICA, FUTA, SUTA)
• Benefit expenses (health, 401(k) matching)
• Liability clearing accounts (to match net pay and tax withholdings against bank feed clearings)

To help narrow down the best fit, tell me:

• What specific payroll provider are you using (or considering)?
• Roughly how many employees do you have, and are they multi-state?

When a company outsources its payroll (using full-service providers like ADP, Gusto, Paychex, or Rippling) but keeps its general ledger and bookkeeping in-house, the primary goal of an accounting system is seamless journal entry mapping and clean reconciliation.

The top accounting systems that integrate cleanly with major outsourced payroll providers include:

• QuickBooks Online (QBO) / QuickBooks Desktop Enterprise
  • Integration Strength: Widely considered the gold standard for third-party compatibility. Almost every major payroll provider—including Gusto, ADP, Paychex, and OnPay—builds a native, direct API integration specifically for QuickBooks.
  • How it works: Once mapped to your chart of accounts (splitting gross wages, employer taxes, and benefit deductions), the payroll provider automatically pushes a customized journal entry or general ledger summary into QBO each pay period, matching the cash disbursement cleanly against your bank feed.
• Xero
  • Integration Strength: Exceptionally strong cloud-based ecosystem with robust API support for external apps.
  • How it works: Gusto, ADP, and OnPay offer direct, automated data syncs into Xero. Xero’s flexible tracking categories allow in-house bookkeepers to easily map payroll expenses by department, location, or project directly from the outsourced data feed.
• Sage 50 / Sage Intacct
  • Integration Strength: Best for mid-market and manufacturing/distribution companies with complex inventory or multi-entity structures.
  • How it works: While smaller systems rely on basic app-store connectors, Sage Intacct uses robust dimensions and custom integrations to ingest detailed GL summaries from enterprise payroll partners like ADP (Workforce Now) or Paychex Flex without manual intervention.
• NetSuite
  • Integration Strength: The leading choice for upper mid-market and scaling enterprises.
  • How it works: NetSuite handles advanced multi-subsidiary accounting. Major enterprise payroll providers support custom connectors or middleware (like Celigo or Boomi) to feed complex, segmented payroll journal entries directly into NetSuite's general ledger.

To help narrow down the ideal fit, could you share:

• Which specific payroll provider you are using (or considering)?
• Your company size / employee headcount?

I can give you more details on how their specific mapping works for journal entries.

Yes. If payroll is outsourced but your accounting team keeps the GL/bookkeeping in-house, I’d prioritize accounting systems with mature payroll journal integrations rather than systems that require importing payroll reports manually.

Best fits

The standout combination: Xero + Gusto

If you're talking about a relatively straightforward business with an in-house bookkeeper/accounting team, Xero + Gusto is probably the cleanest separation of responsibilities.

Gusto can push payroll information into Xero automatically, including wages, taxes, deductions, contributions and reimbursements. Xero specifically describes the workflow as mapping Gusto payroll items to the Xero chart of accounts and then reviewing the resulting payroll journal before posting it to the GL.

That means:

Payroll provider: runs payroll, calculates/files taxes, pays employees
↓
Integration: creates payroll accounting entries
↓
In-house accounting: reviews, reconciles and closes the books

That's generally the architecture I'd want.

QuickBooks Online is the safest choice for breadth

If you don't know which payroll provider you'll ultimately use, QuickBooks Online is probably the safest accounting-platform choice because of its enormous payroll/integration ecosystem. Intuit's current documentation, for example, specifically supports bringing employee/pay history from ADP, Paychex and Gusto into QuickBooks.

The bigger advantage isn't just the existence of an integration—it's finding a payroll vendor that can post a properly mapped payroll journal to your existing QBO chart of accounts rather than forcing the accounting team to reconstruct payroll from a report.

If you're choosing the payroll provider too

I'd roughly rank the pairings:

1. QBO + Gusto — easiest/small-to-midsize
2. Xero + Gusto — arguably the cleanest dedicated accounting/payroll separation
3. QBO + Paychex — good when payroll/HR needs are more substantial
4. QBO + ADP — strong for growing organizations and more complex payroll
5. Sage Intacct + ADP/Paychex/UKG — stronger choice once finance/reporting complexity warrants an ERP
6. NetSuite + enterprise payroll provider — for larger/multi-entity organizations

One important distinction: "integrates" doesn't necessarily mean "cleanly integrates." Before selecting a provider, I'd have the payroll vendor demonstrate an actual payroll run flowing into a test GL. Specifically check whether it handles department/class/location dimensions, employer taxes, benefits, 401(k), garnishments, PTO, reimbursements, payroll liabilities, and clearing-bank reconciliation without manual journal construction.

If you tell me roughly company size (employees), industry, number of entities, and which payroll providers you're considering (ADP, Paychex, Gusto, UKG, Rippling, etc.), I can narrow this to the 2–3 best accounting/payroll combinations.