# Retainer or fixed project: how to decide | abuenoben > A decision rule for agencies and teams choosing between monthly capacity, fixed scope or ongoing support. Canonical URL: https://abuenoben.com/en/guides/retainer-or-fixed-project Language: en [All guides](/en/guides) A decision rule for agencies and teams choosing between monthly capacity, fixed scope or ongoing support. 2 min ยท Updated 2026-09-05 By [Armando Bueno Ben](/en/about) There is no universally better model. The right choice depends on how often priorities change, whether the outcome can be accepted objectively and who carries uncertainty. 01 ## Fixed project Use it when there is a concrete piece, a date, known dependencies and an acceptance criterion. The price covers defined scope and assumptions. - Landing, integration, API or release with a defined outcome. - An owner available to accept milestones. - Changes handled as scope changes. 02 ## Monthly retainer Use it when several small or medium fronts exist and priority changes during the month. It buys capacity and judgment, not an unlimited task list. - Agency peaks and technical presales. - Variable evolutives, QA and integrations. - Visible priority and consumption. 03 ## Support and evolution Use it when a live product needs continuity. It should distinguish emergencies, fixes, improvements and out-of-window work; it is not the same as 24/7 availability. 04 ## The deciding question If you can describe what counts as done, a fixed project probably fits. If you can only prioritize work as it appears, you need monthly capacity. If the system is already live and needs continuity, you need support rules. A short diagnostic can also reduce uncertainty before selecting the longer-term model. 05 ## Two similar requests, two different models Illustrative example: building a landing page with approved design, one form and a documented integration allows a defined delivery. A fixed project can fit if dependencies are available and someone can accept the work. Adding a second integration later would be a change to assess. Handling corrections across several websites while priorities emerge requires choosing the work order during the period. A retainer reserves capacity, records usage and makes it possible to review what has been resolved. Agree a notice point before capacity runs out instead of assuming every urgent request is included. 06 ## What to compare beyond the amount - The outcome or capacity purchased and the working window. - Who prioritises and how a larger task is approved. - How time, blockers and pending work are recorded. - Agreed expiry, carryover and post-delivery support terms. - What happens if an initial review finds that scope still needs definition. Prepare the engagement - [How to outsource development without losing client control](/en/guides/outsource-development-without-losing-client-control) - [What a white-label development agreement should cover](/en/guides/white-label-development-agreement) - [Technical brief checklist for agencies](/en/guides/agency-technical-brief-checklist) Useful next step [See the full comparison](/en/collaboration) ## If the model is unclear, start with the blocker. The first reply can recommend a frame before an estimate is prepared. [Ask for a recommendation](/en/contact#contact-form-shell)