Guideline provides 401(k) programs to small and medium sized businesses. Recently, Guideline advertised that – for users of the Gusto online payroll and human resources platform – it is “Gusto's #1 retirement partner” and the “Most popular 401(k) with Gusto customers.” The basis for Guideline's claims is that more Gusto customers have 401(k) plans with Guideline than any other 401(k) provider on the Gusto platform. Sounds pretty good, right?

A competitor of Guideline, Human Interest , challenged the claims at the National Advertising Division , arguing that the claims were false and misleading because, in 2025, more Gusto customers chose to sign up for Human Interest's 401(k) plans than chose to sign up for Guideline's plans. Sounds like Human Interest is also pretty popular?

So, wh

See Full Page