Fixed Per Transaction
An incentive structure that pays a flat fee per transaction, regardless of transaction size or item count.
Last updated: April 9, 2026
Fixed Per Transaction is an incentive structure that pays a flat fee for each qualifying transaction, regardless of how large the transaction is or how many items it contains. One conversion equals one fixed payout.
When a customer converts, Siren creates an obligation for the configured flat amount. The transaction could be $10 or $10,000. The commission is the same.
How it works
If the incentive is set to $25 per transaction, every qualifying conversion generates a $25 obligation. A customer who buys one $50 product and a customer who buys ten $500 products both earn the collaborator the same $25. Line item filters still apply for determining whether a transaction qualifies at all, but once it does, the payout is flat.
Where this works
Flat-fee commissions work best when the value of a conversion is roughly uniform and you want a predictable cost per sale. They’re also the right choice when you’re rewarding actions that don’t have a clean transaction value, like lead submissions.
The refer a friend program recipe pays a flat reward for each referred customer, which keeps the program simple for participants and gives you predictable marketing costs. The pay per lead affiliate program recipe applies the same flat-fee model to form submissions, paying for leads rather than sales.
This structure also outperforms percentage-based commissions when your store runs heavy discounts. Percentages shrink with every discount, which can frustrate affiliates who still did the work of driving the sale. A flat fee insulates them from price changes.
When to avoid this
If sale sizes vary dramatically and you want affiliates to be motivated by larger carts or premium products, use Percentage of Transaction instead. A flat fee gives affiliates no reason to push higher-value products over cheaper ones.
It’s also a poor fit for programs where each sold unit has roughly the same profit margin but transactions vary in quantity. In that case, Fixed Per Product scales the payout with volume while keeping the per-unit economics predictable.