1. The client letter (plan sponsor notice)
Send on your letterhead, one per plan, before the next plan-year audit starts. Keep it short; sponsors read the first paragraph.
Dear [Sponsor contact], After [N] years of auditing the [Plan name], our firm is stepping back from employee benefit plan audits so that we can focus on [tax and advisory work]. Your plan's audit for the [2026] plan year will need a new independent auditor. We have arranged an introduction to [Licensed firm name], a CPA firm whose practice is limited to retirement plan audits. They will contact you only if you say yes to this letter. You are free to choose any auditor. With your written permission we will share our prior-year audit files with the firm you select so that the transition costs you as little time as possible. Please reply to this letter or sign the enclosed consent by [date]; if we do not hear from you within 90 days we will treat that as consent to transfer the files to the successor you choose. Nothing else about our work for [Company] changes. Sincerely, [Owner], CPA