ENGAGEMENT

Retainer

Recurring monthly engagement where the vendor reserves a defined capacity in exchange for a predictable fee.

Last reviewed: 2026-05-24 byKevin Riedl wiki β†—

A retainer is a subscription to a vendor’s time. You pay every month; in return you get a defined number of days or a defined team capacity. The exact scope shifts; the availability does not.

Retainers work well when the work is ongoing and the priorities change too fast for a Statement of Work to keep up. Product teams use retainers for design partners, engineering teams use them for fractional senior roles, and almost every legal counsel arrangement is a retainer.

The risk is the inverse of T&M: the vendor gets paid even when there is no work. Smart customers attach a "reasonable use" clause and review the retainer quarterly to confirm capacity is being used. If utilisation is below 60%, the retainer is the wrong shape and you want a per-engagement SoW instead.

// FAQ

FAQs

FAQs

Retainer when the priorities shift faster than you can write a scope. SoW when there is a clear deliverable. Most companies start with retainers because it feels flexible, then realise they are paying for capacity that goes unused. Audit utilisation every quarter.
If utilisation is below 60%, you are overpaying for availability you do not use. If it is above 95%, the vendor has no slack for the work that matters and you are running them as staff augmentation. Healthy retainers sit at 70 to 85%.
Depends on the contract. Most retainers require 30 to 90 days notice; some carry a minimum-term clause. Wavect’s Fractional Co-Founder model is the outlier: cancel any week, no notice. Most of the industry is not that flexible.