Guideline's flat-fee 401(k) bet ends inside Gusto after 2025 acquisition

Guideline is a fintech that helps small and medium businesses set up and run 401(k) retirement plans. It was founded in 2015 by Kevin Busque, previously a co-founder of Taskrabbit, on the observation that most small employers offered no retirement plan because traditional 401(k)s were sold by advisors and priced as a percentage of assets under management, which made small plans uneconomical. Guideline's answer was software-only administration at a flat per-employee fee.

From 2016, Gusto — the payroll and HR platform serving the same small-business customers — offered Guideline plans through a partnership, and Guideline also connected to other payroll providers such as ADP, Intuit, Paylocity, TriNet, Block and Rippling. The model scaled: Guideline raised $340M, was valued at $1.15B in a 2021 round, employed more than 400 people, and reached $140M in annualized revenue by January 2025.

As U.S. states began requiring employers to offer retirement plans, 401(k) coverage became a feature payroll platforms wanted to own rather than rent. Gusto — with 400,000+ customers and a $9.3B valuation — agreed to acquire Guideline on 2025-08-27; TechCrunch later reported, from sources, a price near $600M and a plan to divest Guideline accounts tied to rival payroll providers, both disputed by Guideline. By 2025-11-03 customers were receiving emailed options about the move, and Guideline's joining-Gusto FAQ was live and drew 121 points and 115 comments on Hacker News.

The acquisition took effect and Guideline now operates inside Gusto: the FAQ promised unchanged accounts, investments, statements and fees, plus single sign-on with Gusto credentials, and related pages show the offering being presented as Gusto Retirement Pro. The startup's independent existence is over — its flat-fee 401(k) platform became the retirement layer of the payroll bundle for the same small businesses it had served for a decade.