Best HR and Payroll Systems for US Companies With 100-500 Employees

A company with 100 to 500 people seldom runs on one system. There's a payroll tool billed per head. A separate HRIS holds records and time off. Performance reviews live in another app, and benefits sit in a broker's portal. Each renews on its own schedule, each charges its own per-seat fee, and none of them share a clean set of employee data. Finance watches the invoices pile up. HR spends payroll week reconciling numbers between apps that were never built to talk to each other. Closing that gap is the whole promise of the best HR and payroll software for small business.

The right platform at this size fixes the bill and the busywork at once: one platform that runs payroll, files the taxes, and holds the org's people data in a single place. This guide ranks eight systems for US teams in the 100 to 500 range, weighing native payroll, setup speed, price, and how far each one scales before you outgrow it.

HR and payroll systems for 100 to 500 employees at a glance

Tool	Best for	Starting price
HiBob (Bob)	One core for HR and native US payroll that scales past 100	Custom (book a demo)
Gusto	Small teams that want payroll and benefits running fast	$49/mo + $6/employee
BambooHR	HR-first teams adding payroll as a module	Custom quote
ADP RUN	Very small teams that expect to move up an ADP tier	Custom quote
Paychex Flex	Teams that want a dedicated payroll specialist on call	From $39/mo + $5/employee
Justworks	Lean teams that want a PEO to co-manage compliance	Custom quote
OnPay	Budget-minded teams with straightforward US payroll	$49/mo + $6/employee
Rippling	Tech-forward teams wiring payroll into IT and apps	Custom quote

How we ranked HR and payroll systems for 100 to 500 employees

Companies in this range need more than a payroll app and less than an enterprise HCM rollout. Our ranking weighs what matters at that size. Native, full-service payroll came first, then setup speed and price transparency, and last, how far each platform scales before a team outgrows it. We drew on published pricing and documented user reviews on G2 and Capterra rather than first-hand testing. Support quality and multi-state US tax coverage counted too, since a filing error at 300 employees costs far more than at 20. Benefits administration and how each vendor handles a mix of W-2 and 1099 workers fed into the scoring, because a team this size runs several employment types at once.

1. HiBob

For a team crossing 100 employees, Bob answers the problem this list opens with: too many tools, too little shared data. HiBob runs native, full-service US payroll on the same core that holds employee records and analytics. The payroll suite covers flexible pay cycles plus federal and state tax filing, pulling from the same people data behind every other HR workflow. One system pays your team and stores that data, so payroll week stops being a reconciliation exercise.

Setup is the other draw. Most customers go live in weeks, not the months a legacy suite tends to demand, and the interface earns the daily use that heavier systems never get. Bob's suite design lets a 120-person company start on Core plus payroll, then add talent and planning modules as it grows toward 500 and past it, with no re-platforming.

Reviews back the experience: 4.5 on G2 from 1,811-plus ratings, plus 4.6 on Capterra. Its honest catch is commercial: Bob keeps prices off the page, so a figure means talking to sales first.

1. Gusto

Gusto is the default for a lot of US small businesses, and for good reason. Payroll runs are quick, tax filing is automatic across federal and state levels, and benefits (health plans and 401(k)) sit inside the same dashboard. Published pricing starts at $49 a month plus $6 per employee, which is transparent next to the quote-only enterprise suites. Its G2 score is a strong 4.6 from 10,000-plus reviews.

The friction shows up as you scale toward the top of this bracket. G2 reviewers flag payroll hiccups and login problems more often than the marketing suggests, and support can lag when a run goes wrong, which stings more at 300 employees than at 15. Customization is also thinner than mid-market HR teams expect. Gusto suits a lean, US-only team that wants payroll handled without fuss, though a 400-person company with layered approvals and deeper HR needs tends to find the ceiling.

1. BambooHR

BambooHR built its reputation on approachable core HR: onboarding, records, and time-off tracking that HR admins enjoy using. It carries a 4.4 on G2 from 5,000-plus reviews, most praising the clean interface. For a 100 to 500 team that wants to fix HR first and worry about payroll second, it's a reasonable shortlist entry.

The payroll story is the caveat. BambooHR runs payroll as an add-on on top of the HR core rather than the product's center of gravity, so teams that put payroll first sometimes find it thinner than a payroll-native platform. Reviewers also cite limited customization: the workflows and fields don't bend as far as a growing, process-heavy company needs. BambooHR works when HR is the priority and payroll is a bolt-on, less so when native, full-service payroll has to anchor the whole system.

1. ADP RUN

ADP is the most recognized name in US payroll, and RUN is its small-business product. Tax filing and direct deposit carry ADP's decades of payroll infrastructure, with compliance alerts on top, and the brand reassures finance leaders who want an established provider. G2 gives ADP a 4.2 across about 4,200 reviews.

The fit issue for this bracket is size. RUN targets small employers, and ADP steers growing companies toward Workforce Now once headcount climbs, so a team heading past 100 may buy into a product it soon outgrows. Reviewers also report clumsy navigation and support that's hard to reach when something breaks. Add-on modules pile onto the base cost, and pricing stays quote-only, so comparing ADP against a published per-employee rate takes a sales call. RUN makes sense for a smaller team already committed to the ADP ecosystem, with a plan to move up as it grows.

1. Paychex Flex

Paychex pairs full payroll and HR with a service model built around a named specialist, which appeals to companies that would rather phone a person than file a ticket. Its published entry pricing starts around $39 a month plus $5 per employee, and the platform extends into HR and time tracking as needs grow. For regulated industries that value hand-holding, it's a common pick.

Reviews complicate the support promise. Paychex holds a 4.1 on G2, the lowest of the established names here, and users cite inconsistent customer support alongside costs that climb as add-ons stack up. What starts as a tidy per-employee rate can balloon once you layer on the modules a 300-person company needs. Paychex earns its place for teams that prize a support relationship, though the value math deserves a close look before signing.

1. Justworks

Justworks runs payroll through a PEO model, handling benefits and payroll tax as a co-employer, compliance included. Small teams like the simplicity and the access to big-group benefits rates, and its G2 score sits at 4.6 from 1,100-plus reviews, with support and ease of use drawing the most praise.

The trade-offs matter more as you scale. Reviewers point to missing features and integration gaps, so a company that wants payroll wired into its wider HR and app stack can hit walls. Some also report support slipping under load. The co-employment structure that simplifies life at 40 employees can feel constraining at 400, when an HR team wants direct control over its own systems and data. Justworks fits a smaller team happy to outsource the back office, less so a company building an owned, integrated HR core.

1. OnPay

OnPay keeps payroll simple and affordable: full-service tax filing and unlimited pay runs, with benefits administration included, at a flat $49 a month plus $6 per employee. It handles W-2 and 1099 workers and supports multi-state payroll, and it earns a reputation for accurate compliance without hidden fees. For a cost-conscious team that wants clean payroll and light HR, it's a value standout.

Where it lags is depth and polish. There's no dedicated mobile payroll app, and the interface feels more functional than modern next to newer platforms. The HR tooling covers basics rather than the layered workflows a 400-person company leans on, so OnPay tends to fit the lower end of this range better than the upper. It's a strong choice when price and simplicity outrank breadth, and a tighter fit for a 120-person team than one closing in on 500.

1. Rippling

Rippling bundles payroll, HR, and IT management in one system, and it's the highest-rated platform here at 4.8 on G2 from 12,000-plus reviews. For a company that wants to provision laptops and payroll from a single admin panel, the breadth is genuine.

That breadth comes with a learning curve. Reviewers cite a steep ramp and, despite the feature count, still flag gaps for specific workflows. The IT-plus-HR framing also means people-experience features can feel secondary to provisioning and device control. Rippling rewards a technical admin who'll invest in setup, and it's a heavier lift than a team wanting HR and payroll without the IT layer may want to take on. Pricing is quote-based.

Choosing HR and payroll software for a growing 100 to 500 team

At 100 to 500 employees, the sweet spot sits between two extremes. An SMB payroll app like Gusto or OnPay pays people well but runs shallow on HR and bends only so far. A legacy suite like ADP or Paychex carries the depth but arrives with quote-only pricing and interfaces that feel their age, with support that tests your patience. Employee experience matters here too, because a 300-person team lives in the system every day, and a clunky one drains the hours it was meant to save. The best HR and payroll software for small business at this size gives you native payroll and real HR depth on one modern core, priced and built for a company still growing.

That's why Bob tops the list. It runs full-service US payroll and unified people data on a single platform, goes live in weeks, and adds talent and planning as you climb toward 500 without a rebuild. You trade public pricing for a demo, but for a team tired of stitching overlapping tools together, one core that grows with you is the cleaner math.

Payroll for 100 to 500 employees: FAQ

What payroll software is best for a mid-size business?

It depends on how much HR you need alongside payroll. A team that wants clean, automated pay runs and little else does well with a focused tool like Gusto or OnPay. A company that wants payroll and a full HR system on one platform, with room to grow, should look at an all-in-one such as Bob, which pairs native US payroll with unified people data. Match the choice to whether payroll or HR depth is your bigger gap.

How much does HR and payroll software cost for 100 to 500 employees?

Most platforms price per employee per month on top of a base fee. Published SMB rates run from $40 a month plus $6 per employee at OnPay to $49 plus $6 with Gusto, while the larger suites (ADP, Paychex, BambooHR) quote custom pricing that shifts with your modules and headcount. Budget for setup and add-ons too, since the sticker rate seldom reflects the full bill once you add benefits and support tiers.

What's the difference between full-service and self-service payroll?

Full-service payroll means the provider files and pays your federal and state payroll taxes for you, issues year-end forms, and handles the compliance work. Self-service payroll calculates the numbers but leaves the filing and payments to you. Most companies past 100 employees choose full-service, because the time saved and the lower risk of a filing error outweigh the small premium.

Which payroll software is most used in the US?

ADP and Paychex process payroll for a huge share of US businesses and rank among the most used by volume, above all among larger and legacy accounts. Gusto has become a default for newer small and mid-size teams. Most used doesn't mean best fit, though: the right pick depends on your size and how much HR depth you need.

How long does it take to set up HR and payroll software?

Timelines range from a few days for a simple payroll-only tool to several months for a legacy suite with heavy configuration. Modern all-in-one platforms land in between: Bob, for instance, gets most customers live in weeks, since one data model covers HR and payroll and there's no integration to wire up between separate systems. Migration effort scales with how clean your existing employee data is.

Can one system handle both HR and payroll for 500 employees?

Yes. All-in-one platforms are built to run HR and payroll for a 500-person company on a single system, which removes the sync work between separate tools. Bob is one example, carrying native US payroll on the same core as records and analytics, then extending into talent and planning as you scale. The gain is one source of employee data instead of several that drift apart.

Do you need native US payroll, or is an integration enough?

Native payroll runs inside the HR platform itself, so pay and people data share one system and one login. An integration links a separate payroll tool to your HR system, which works but adds a connection to maintain and a second vendor to manage. For US-only teams, native payroll is often cleaner; companies with staff in several countries mix native payroll where they can with connected providers elsewhere.