Project-based billing is a rollercoaster—feast or famine, unpredictable cash flow, constant sales cycles. Retainer billing smooths everything out. Here's how to structure and manage retainers effectively.
Why Retainers Work for Agencies
Retainers provide:
- Predictable revenue: Know what's coming in each month
- Stable cash flow: Bill at the beginning of the month, not after work is done
- Deeper client relationships: Ongoing work builds understanding and trust
- Reduced sales overhead: Less time pitching, more time delivering
Structuring Your Retainers
Fixed Monthly Retainer
Client pays a set amount each month for a defined scope of work. This is the simplest model—clear expectations on both sides.
Best for: Ongoing services with consistent workload (marketing, maintenance, support).
Hourly Retainer with Cap
Client commits to a minimum number of hours, paid whether used or not. Additional hours billed at your hourly rate up to a cap.
Best for: Work with variable demand where clients want flexibility.
Value-Based Retainer
Price based on the value delivered rather than hours or tasks. Higher risk, higher reward—requires strong trust and clear metrics.
Best for: Strategic work where outcomes can be measured (lead generation, revenue growth).
Billing Best Practices
Bill in Advance
Always bill at the beginning of the retainer period, not the end. This improves cash flow and signals that this is a commitment, not a project.
Automate the Billing
Set up recurring subscriptions in Stripe so retainer payments happen automatically. No manual invoicing each month, no chasing payments.
Be Clear About Scope
Retainer agreements should specify what's included. Without boundaries, scope creep leads to resentment on both sides.
Handle Overages Gracefully
When work exceeds the retainer scope, have a clear process. Some agencies require approval for additional charges; others flex within a reasonable range.
Common Retainer Mistakes
Underpricing to Win the Deal
A retainer that doesn't cover your costs is worse than no retainer. Price based on value and capacity, not on what the client seems willing to pay.
Not Tracking Hours
Even with fixed retainers, track time spent. This helps you know if the retainer is profitable and provides data for future pricing.
Letting Unused Hours Roll Over Indefinitely
Rolling over unused hours creates liability and encourages clients to "bank" time for occasional large requests. Limit rollover or don't offer it.
Transitioning Clients to Retainers
Existing project clients can become retainer clients. After a successful project:
- Identify ongoing needs (maintenance, iteration, support)
- Propose a retainer that covers those needs
- Position it as continuity—you already understand their business
Many clients appreciate the offer. They know finding another provider means starting from scratch.
Tools for Retainer Billing
Stripe's subscription billing handles the payment side. For management and visibility, a billing portal like Conto lets you see all retainer clients in one place, track payment status, and handle changes without diving into Stripe's dashboard.