OnPay vs Paychex Flex

Side-by-side from the Top 11 ranking of The 11 Best Payroll Software for SMBs (2026). Last verified May 31, 2026.

The short answer

OnPay ranks higher on Top 11 (#4 vs #6) for Small business owners running payroll without in-house HR. Offers a single, transparently priced plan with great support and features for niche industries.

At a glance

OnPayPaychex Flex
Top 11 rank#4 / The 11 Best Payroll Software for SMBs (2026)#6 / The 11 Best Payroll Software for SMBs (2026)
Score (out of 9.4)8.68.2
Best forNiche industry featuresAll-in-one HR services
Pricing$ ($46+/mo)$$$ (Varies by quote)
HQAtlanta, USARochester, USA
Founded20071971

OnPay

Offers a single, transparently priced plan with great support and features for niche industries.

onpay.com

See full entry in The 11 Best Payroll Software for SMBs (2026)

Paychex Flex

A comprehensive HR platform from an industry veteran, ideal for businesses needing more than just payroll.

www.paychex.com/paychex-flex

See full entry in The 11 Best Payroll Software for SMBs (2026)

Methodology and scoring weights live at /methodology. No vendor pays for placement — see about.