Every CPA firm owner we talk to has the same relationship with payroll. They know their clients need it. They know offering it creates sticky client relationships. And they know it is a compliance minefield that generates thin margins and disproportionate risk.
The math looks simple on paper. Client has 25 employees, you run payroll twice a month, charge a fee, done. But then you add multi-state withholding for remote employees, mid-year hires in new jurisdictions, garnishments, benefits deductions, quarterly filings, W-2s, and the occasional panicked call because someone's direct deposit did not go through.
Suddenly that "simple" payroll client is consuming hours of staff time every pay period. And if you make an error, the penalties land on your desk, not theirs.
This is why more CPA firms are outsourcing payroll processing rather than handling it in-house. Not outsourcing the client relationship (you still own that), but outsourcing the production work. Let us break down what it actually costs.
Before comparing costs, we need to distinguish between two fundamentally different approaches.
Model 1: DIY Platform (Gusto, ADP Run, Paychex Flex, etc.) The CPA firm subscribes to a payroll platform and processes payroll internally. The platform handles calculations, tax filings, and direct deposits. The firm's staff handles setup, ongoing processing, and troubleshooting.
Model 2: Outsourced Processing (Madras, specialized payroll outsourcing firms) The CPA firm partners with an outsourcing provider that handles the actual payroll processing. The firm maintains the client relationship. The provider handles data entry, processing, compliance, and filing using the platform of choice.
Most CPA firms start with Model 1 and migrate to Model 2 as their payroll client base grows. The crossover point where outsourcing becomes clearly more economical is usually around 15-20 payroll clients or 200+ total employees across all clients.
Let us look at what the major platforms charge CPA firms in 2026. These are accountant/partner program rates, which are typically discounted from retail pricing.
Base fee: $0/month platform fee for accountant partners (retail clients pay $40-$80/month)
Per employee: $6-$12/employee/month depending on tier
What is included: Payroll processing, direct deposit, basic tax filings, W-2/1099 preparation, employee self-service portal, basic benefits administration
What costs extra: State tax registration in new states ($50-$100 per state), international contractor payments, R&D tax credit calculations, priority support
Example: 25-employee client Platform: $0/month (accountant partner)
Per employee: 25 x $8 = $200/month
Annual platform cost: $2,400
Gusto is the most CPA-firm-friendly platform in 2026. Their accountant dashboard is clean, their API integrates well with QBO and Xero, and their support for accountant partners is above average. The limitation: Gusto is built for small to mid-size employers. Once a client exceeds 100-150 employees or has complex benefit structures, you will hit walls.
Base fee: $59-$79/month per client
Per employee: $4-$6/employee/month
What is included: Payroll processing, tax filings, direct deposit, new hire reporting, garnishment processing, basic HR tools
What costs extra: Time and attendance ($2-$4/employee/month), HR support, background checks, workers comp administration, enhanced reporting
Example: 25-employee client Platform: $69/month
Per employee: 25 x $5 = $125/month
Total: $194/month
Annual platform cost: $2,328
ADP is the incumbent. They process payroll for roughly 1 in 6 US workers. Their infrastructure is battle-tested. The downside for CPA firms: ADP's interface is clunky compared to Gusto or Rippling, and their pricing structure has more add-ons that inflate the actual cost. Getting a straight answer on total cost requires navigating a sales process that feels like buying a car.
Base fee: $39-$59/month per client
Per employee: $5-$7/employee/month
What is included: Payroll processing, tax administration, direct deposit, W-2/1099 prep, basic time tracking
What costs extra: HR administration, benefits, workers comp, advanced reporting, dedicated payroll specialist
Example: 25-employee client Platform: $49/month
Per employee: 25 x $6 = $150/month
Total: $199/month
Annual platform cost: $2,388
Paychex occupies a middle ground between Gusto's simplicity and ADP's enterprise features. They are solid for CPA firms serving clients with 10-75 employees. Their accountant program has improved in recent years, though it still trails Gusto in terms of partner experience.
Base fee: $0 platform fee (employee management is the base, payroll is an add-on)
Per employee: $8-$12/employee/month for the payroll module
What is included: Payroll, tax filings, benefits administration, device management, app provisioning (if using the full platform)
What costs extra: International payroll, compliance monitoring, advanced workflows
Example: 25-employee client Per employee: 25 x $10 = $250/month
Annual platform cost: $3,000
Rippling is newer to the accountant channel but growing quickly. Their strength is the unified platform (HR, IT, payroll, benefits in one system). For tech-forward CPA firms with tech-forward clients, it is worth evaluating. The catch: it is more expensive per employee than Gusto or ADP, and the full value only materializes when the client uses the broader platform beyond just payroll.
Platform costs are only part of the story. The bigger cost is the labor your firm dedicates to payroll processing.
Here is what actually happens when a CPA firm processes payroll in-house using a platform:
Per pay period, per client:
Total per pay period per client: 45-115 minutes, depending on complexity.
For a client running biweekly payroll, that is 24-50 hours per year of staff time. At a fully loaded staff cost of $30-$45/hour, that is $720-$2,250 per year in labor, per client.
Quarterly and annual tasks add more:
Total annual labor cost per client (25 employees, biweekly payroll): $1,200-$3,500.
Add the platform cost ($2,300-$3,000), and the total cost to your firm is $3,500-$6,500 per client per year, or $11.67-$21.67 per employee per month.
Now here is the question: what are you charging the client? If you are charging $200-$300/month for a 25-employee payroll, you are collecting $2,400-$3,600/year. Against costs of $3,500-$6,500, you might actually be losing money.
This is the dirty secret of CPA firm payroll services. Many firms are subsidizing payroll with margins from tax and bookkeeping work because they know payroll creates client stickiness. It is a rational strategy. It is also unsustainable at scale.
Now let us look at outsourcing the processing work to a provider like Madras.
Per employee per month: $3-$6 (depending on volume and complexity)
What is included:
What the CPA firm handles:
Example: 25-employee client Outsourced processing: 25 x $4.50 = $112.50/month
Platform cost (Gusto, accountant partner): $200/month (25 x $8)
Total cost to the firm: $312.50/month or $3,750/year
Your labor cost drops to approximately 15-20 minutes per pay period (reviewing and approving the payroll run prepared by Madras) instead of 45-115 minutes doing the whole thing yourself. That is a reduction of 70-80% in staff time.
If you charge the client $250/month ($3,000/year), your margin is: Revenue: $3,000
Costs: $3,750 (platform + outsourced processing + minimal firm labor)
Still thin. But if you negotiate accountant-partner pricing with Gusto or use a lower-cost platform, and if you process at higher volumes (which reduces the per-employee outsourcing rate), the economics improve:
At scale (200+ employees across multiple clients): Outsourced processing: $3.00/employee/month
Platform: $6/employee/month (volume-discounted)
Total cost: $9/employee/month
Charge to client: $12-$15/employee/month
Margin: 25-40%
Payroll becomes profitable at scale when the processing is outsourced. It remains a margin drag when processed in-house.
The per-employee cost differences look modest. But multiply by hundreds of employees across your client base and the annual impact is significant. A CPA firm processing payroll for 500 employees across 30 clients saves $12,000-$36,000 per year by outsourcing the processing work. More importantly, they free up hundreds of hours of staff time for higher-value work.
Multi-state payroll is where the simple pricing models break down. And in 2026, with remote work now permanent for many companies, multi-state is the norm rather than the exception.
A single-state payroll for 25 employees is straightforward. The same company with employees in 8 states requires:
Multi-state add-on costs: Most platforms charge for state tax registration in new states ($50-$100 per state, one-time). The ongoing cost is in the complexity of processing, not the platform fees.
For DIY firms, multi-state adds 30-60 minutes per pay period for a complex client. That is an additional $15-$45 per pay period, or $390-$1,170 per year.
For outsourced providers like Madras, multi-state processing is included in the standard per-employee rate for most clients. We handle the filings, the reciprocity tracking, and the compliance monitoring. Where costs increase is when a client adds new states frequently (growing companies with active hiring in new markets), which requires new registrations and ongoing monitoring.
Our recommendation: If your firm serves clients with employees in 3+ states, outsourcing payroll processing is almost always the right call. The compliance risk of getting multi-state payroll wrong (penalties, interest, amended filings) far exceeds the cost of outsourcing.
1099 processing hits CPA firms in January like a freight train. Every client needs their 1099s prepared, reviewed, and filed by January 31. For firms with dozens of clients, each with dozens of contractors, this is hundreds or thousands of 1099s competing for attention at the exact moment tax season is ramping up.
1099 processing costs:
The per-form cost of outsourcing 1099s is slightly higher than DIY, but the total cost (including labor) is lower because you are not using expensive US staff time to chase W-9s and enter data. W-9 collection alone can consume 10-15 minutes per contractor for firms that do not have a systematic process.
At Madras, we handle the entire 1099 lifecycle: W-9 collection from contractors, TIN verification, payment data compilation, form preparation, review, e-filing, and corrections. For CPA firms managing 1099s for multiple clients, this removes one of the most stressful bottlenecks of the year. Our guide on outsourcing payroll and 1099 services covers this in depth.
Let us model a CPA firm's payroll practice at three scales.
In-house processing: Platform costs: 150 x $8 = $1,200/month
Labor: 10 clients x 2 hours/month = 20 hours x $40/hour = $800/month
Total cost: $2,000/month
Revenue (at $12/employee): $1,800/month
Monthly margin: -$200 (loss)
Outsourced processing (Madras): Platform costs: $1,200/month
Outsourced processing: 150 x $4.50 = $675/month
Firm labor (review/approve): 10 clients x 0.5 hours = 5 hours x $40 = $200/month
Total cost: $2,075/month
Revenue: $1,800/month
Monthly margin: -$275 (small loss, but saves 15 hours of staff time) At this scale, payroll is a loss leader regardless of approach. The value is in client retention and cross-selling. But the outsourced model frees up 15 hours per month of staff time for higher-value work.
In-house processing: Platform costs: 500 x $7 (volume discount) = $3,500/month
Labor: 30 clients x 2 hours = 60 hours x $40 = $2,400/month
Total cost: $5,900/month
Revenue (at $13/employee): $6,500/month
Monthly margin: $600 (10%)
Outsourced processing (Madras): Platform costs: $3,500/month
Outsourced processing: 500 x $3.50 = $1,750/month
Firm labor: 30 clients x 0.5 hours = 15 hours x $40 = $600/month
Total cost: $5,850/month
Revenue: $6,500/month
Monthly margin: $650 (10%), but saves 45 hours/month of staff time The margins are similar, but outsourcing frees up 45 hours per month. At $150/hour realization on tax or advisory work, that is $6,750 in potential revenue from redeployed staff time.
In-house processing: Platform costs: 1,500 x $6 (volume discount) = $9,000/month
Labor: 75 clients x 2 hours = 150 hours x $40 = $6,000/month
Dedicated payroll manager: $5,000/month (allocated)
Total cost: $20,000/month
Revenue (at $14/employee): $21,000/month
Monthly margin: $1,000 (5%)
Outsourced processing (Madras): Platform costs: $9,000/month
Outsourced processing: 1,500 x $3.00 = $4,500/month
Firm labor: 75 clients x 0.5 hours = 37.5 hours x $40 = $1,500/month
No dedicated payroll manager needed
Total cost: $15,000/month
Revenue: $21,000/month
Monthly margin: $6,000 (29%) At scale, the outsourcing advantage is dramatic. The firm saves $5,000/month in direct costs and eliminates the need for a dedicated payroll manager. The payroll practice goes from 5% margin to 29% margin.
If you are considering outsourcing payroll processing, evaluate providers on these criteria:
Platform flexibility. The provider should work with your preferred payroll platform, not force you onto theirs. At Madras, we process payroll in Gusto, ADP, Paychex, and other platforms based on what works for each client.
Multi-state expertise. Ask specifically about their experience with multi-state payroll, reciprocity agreements, and local tax jurisdictions. Errors here create real compliance exposure.
Turnaround time. Payroll has hard deadlines. Your provider needs to process payroll within your window, typically requiring completion 2-3 business days before pay date for direct deposit. Ask about their SLA for turnaround.
Error handling process. How do they handle mistakes? What is the escalation process? Who bears the cost of penalty and interest if an error causes a filing issue? Get this in writing.
Communication structure. You need a clear point of contact and a defined communication process. Payroll questions from clients often need same-day responses. Make sure your provider can deliver that. Our best practices for offshore team management apply directly here.
Data security. Payroll data includes Social Security numbers, bank account numbers, and salary information. Your provider's security protocols need to be robust. Ask about encryption, access controls, background checks on staff, and SOC compliance.
Beyond cost and efficiency, there is a compliance argument for outsourcing payroll processing. Payroll compliance is getting more complex every year. State-level paid leave laws, varying minimum wage requirements, new transparency laws requiring salary ranges, changes to overtime rules. Keeping up with all of this across multiple states and multiple clients is a full-time job.
A dedicated payroll outsourcing provider tracks these changes as part of their core operation. They update processes when laws change, flag clients that are affected, and implement the necessary adjustments. Your firm gets the benefit of their compliance infrastructure without building it yourself.
This does not eliminate your firm's responsibility to the client. But it significantly reduces the risk that something falls through the cracks because your staff was too busy with tax season to notice a state payroll tax rate change.
Transitioning payroll processing to an outsourced provider does not need to be disruptive. Here is the typical process:
Week 1: Provider reviews your current payroll setup (platforms, clients, complexity levels). You provide access to payroll platforms and relevant client information.
Week 2-3: Provider shadows your current process. They process payroll in parallel with your staff, comparing results to ensure accuracy before going live.
Week 4: Provider takes over primary processing. Your staff reviews and approves payroll runs before submission. This review step continues indefinitely as your quality check.
After 30 days: Evaluate. Are the payroll runs accurate? Is communication working? Is the turnaround time acceptable? If yes, expand to additional clients.
At Madras, we typically onboard a CPA firm's first 5-10 payroll clients within 3-4 weeks. From there, we add clients at whatever pace the firm is comfortable with. The goal is a smooth transition that the clients never notice, because the only thing that changes is who enters the data, not who they call with questions.
If payroll is eating your firm's time and margins, we should talk. Visit madrasaccountancy.com to start the conversation.
Will my clients know that payroll is being processed offshore? Not unless you tell them. The payroll runs through the same platform (Gusto, ADP, etc.), direct deposits come from the same source, and your firm remains the client's point of contact. The processing work happens behind the scenes, just as it would if a junior staff member in your office were doing it.
What happens if there is a payroll error? Errors are handled immediately. At Madras, our process includes a pre-submission review checklist that catches the most common errors (incorrect hours, wrong pay rates, missing deductions) before the payroll is submitted for your approval. If an error makes it through to processing, we work with your firm to correct it in the next pay cycle or issue an off-cycle correction. Our error rate across all payroll clients is below 0.3%.
Can outsourced providers handle complex benefits deductions? Yes. We regularly process payrolls with HSA contributions, FSA deductions, 401(k) withholdings (including loan repayments), union dues, and multiple insurance plan tiers. The key is accurate setup in the initial onboarding phase. Once deductions are configured correctly, they process automatically each pay period.
How do you handle garnishments and child support orders? Garnishment processing is included in our standard payroll service. We receive the garnishment order, calculate the correct withholding based on the applicable formula (federal or state, depending on the order type), apply the deduction, and remit payment to the appropriate agency or recipient. We also track multiple garnishments per employee and apply the correct priority rules.
What is the minimum number of payroll clients needed to make outsourcing worthwhile? Economically, even a single payroll client can benefit from outsourced processing if your firm does not have dedicated payroll staff. The real value kicks in at 10+ clients or 150+ total employees, where the time savings become substantial and the cost per employee drops with volume. Most CPA firms that outsource payroll processing with us start with their 5-10 simplest clients, prove the model, and then migrate the rest within 60-90 days.
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