HR and payroll for accountancy practices in the United States
Reviewed by Mellow Editorial Team, HR & payroll content team
Running HR and payroll for an accountancy practice in the US follows the same federal framework as any other employer — but the sector adds specific wrinkles around staff classification, licensing, non-competes, and the seasonal nature of the work that make getting it right more demanding than average.
Classifying your workforce correctly
Accountancy practices commonly rely on a mix of full-time staff, part-time bookkeepers, seasonal tax preparers, and independent contractors. The IRS uses a behavioral control, financial control, and type-of-relationship test to determine whether a worker is an employee or an independent contractor. Misclassifying an employee as a contractor exposes you to back FICA taxes, penalties, and interest.
A seasonal tax preparer who works exclusively for your firm, follows your procedures, and uses your software almost certainly qualifies as an employee — even if the engagement only runs from January through April. Issue them a W-2 by January 31, not a 1099-NEC. Reserve the 1099-NEC for genuinely independent professionals: a freelance IT consultant you hire for one project, for example.
If your practice operates in California, take extra care. California's ABC test sets a higher bar for contractor classification than federal rules, and the state also prohibits most non-compete clauses — meaning any restrictive covenant you ask a California-based accountant to sign is likely unenforceable from day one.
Payroll mechanics for an accountancy practice
Your payroll obligations are the same as any US employer. You withhold federal income tax based on each employee's Form W-4 elections (tax is progressive, running from 10% to 37% across brackets). You also withhold and remit FICA taxes: Social Security at 6.2% of wages up to the annual wage base, Medicare at 1.45% with no cap, and an additional 0.9% Medicare surcharge for high earners whose wages exceed the applicable threshold. You match the Social Security and Medicare portions as the employer.
File Form 941 quarterly to report wages and taxes withheld. Deliver W-2s to employees and file with the SSA by January 31 — a date that falls squarely in your busiest season, so build it into your calendar well in advance.
If you employ CPAs or licensed accountants in multiple states, be aware that state income tax obligations vary significantly. Texas, Florida, and Washington have no state income tax; others impose rates and filing requirements that differ from federal rules. Multi-state payroll means registering as an employer in each state where you have workers, withholding at that state's rate, and in some cases navigating reciprocity agreements for employees who live in one state and work in another.
Managing the seasonal workload spike
Tax season creates a predictable staffing surge. From a payroll and HR standpoint, that means onboarding a cohort of temporary employees on a tight timeline, then offboarding them cleanly. A few practical steps:
- Complete Form I-9 employment eligibility verification before or on day one — no exceptions, even for short-term hires.
- Set clear written offer letters that specify the temporary nature of the role, the anticipated end date, and the pay rate. US employment is generally at-will, but a written letter avoids ambiguity.
- If your state requires pay-frequency disclosures or final-pay timing rules (California, for instance, requires immediate final pay on termination), apply those rules to temporary staff just as you would permanent employees.
Plan your payroll processing calendar around filing deadlines. Running payroll late in early April is a real risk if your HR team is also buried in client returns.
Benefits and leave obligations
There is no federal statutory paid annual leave or sick leave, so your practice has discretion on PTO policy. That said, a growing number of states and cities mandate paid sick leave — check the rules for every location where you employ staff.
For practices with 50 or more full-time equivalent employees, the Affordable Care Act requires offering qualifying health coverage to full-time employees (those working 30 or more hours per week on average). Seasonal employees may count toward that threshold depending on how long the season runs, so model your headcount carefully before peak hiring.
Retirement benefits matter for recruiting in a competitive talent market. A SIMPLE IRA or SEP-IRA tends to suit smaller practices for its lower administrative burden; larger practices may offer a 401(k) with or without an employer match.
Licensing, compliance records, and confidentiality
Accountancy practices have a compliance dimension most other employers do not: state CPA licensing. If you employ CPAs, keep copies of current licenses on file and build license renewal dates into your HR calendar. Letting a CPA's license lapse mid-engagement creates both a regulatory problem and a client service issue.
Because your staff handles sensitive client financial data, your employment agreements should include clear confidentiality provisions and data-handling policies. These are enforceable in all states and are separate from — and not to be confused with — non-compete clauses, which face significant restrictions in several states and are under increasing federal scrutiny.
For practices with remote or hybrid staff spread across states, how Mellow runs payroll across six countries on one platform illustrates how centralizing payroll administration reduces the risk of missing a state registration or filing deadline.
---
Run HR and payroll in United States with Mellow
Mellow brings HR, payroll and 12 AI agents into one platform — built to handle United States properly, with payroll included, from £4 per employee per month. The AI agents don't just answer questions; they generate contracts, run cost estimates and draft letters for you.
- United States payroll software
[Start a free trial →](/register)