Let’s talk about how we can build your commerce project — tailored to your business, powered by Mercur
Deciding your take rate is the strategy question. Configuring how that rate actually applies - flat or tiered, the same for everyone or different per category and per seller, calculated and paid out automatically - is the system question. Most teams underestimate the second.
A marketplace commission structure is only as flexible as the commission engine underneath it. You can design the perfect rate card, but if the platform only supports one flat percentage, your model collapses to the lowest common denominator.
This guide covers the commission structures a marketplace can run, and what a commission engine needs to support them. For the strategic choice of which revenue model to use, see our guide on marketplace monetization models.
What a commission structure actually controls
A commission structure defines how much the operator takes from each transaction and under what rules. It sits between the sale and the seller payout, deciding what the platform keeps.
The structure is not just a number. It answers: does every seller pay the same rate, does it vary by product category, does it change with volume, and can specific sellers have negotiated terms? The more your marketplace grows, the more you need commission rules that differ by seller, category, and volume - not one rate for everyone.
The main commission structures
Marketplaces rarely run a single flat rate for long. These are the structures a mature commission model combines.
Flat commission
Every transaction is charged the same percentage, regardless of seller or category. It's simple to explain and simple to run, which makes it the right starting point for a new marketplace.
The limit shows up as you scale. A flat rate that works for a high-margin category punishes a low-margin one, and a rate that keeps low-margin sellers happy leaves money on the table elsewhere.
Category-specific commission
Different product categories carry different rates. High-margin categories can support a higher commission; low-margin, high-volume categories need a lower one to keep sellers viable.
Category rates let you match your take to the economics of each segment. This is one of the most common structures on marketplaces with a broad catalog, and a capability sellers actively look for when comparing platforms.
Per-seller commission
Individual sellers can have their own rate. A strategic seller you recruited with a preferential deal, a high-volume seller who negotiated down, or a new seller on an introductory rate - each carries terms specific to them.
Per-seller rates turn commission from a fixed policy into a negotiation lever you can use to win and keep the sellers who matter most.
Tiered commission
The rate changes with volume. A seller pays one percentage up to a threshold and a lower one above it, rewarding growth and giving your best sellers a reason to consolidate on your platform.
Tiered structures align the operator and the seller: as the seller sells more, the rate they actually pay drops, which reduces the incentive to move volume elsewhere.
Hybrid structures
Real marketplaces combine these. A base category rate, overridden by per-seller deals, with volume tiers on top. The commission a given transaction pays is the result of several rules resolving together.
This is where a weak commission engine breaks. Combining category, seller, and volume rules on the same transaction is only possible if the platform was built to resolve layered commission logic.
What the commission engine has to do
Behind any structure sits an engine that calculates, applies, and settles commission. Three jobs define whether it can run your model.
Calculation. The engine resolves the correct rate for each transaction from the applicable rules - category, seller, and volume together - and computes the split in real time.
Application at order splitting. When one buyer order contains items from several sellers, commission is applied per seller sub-order, not to the whole cart. This ties directly to how the platform handles order splitting across multiple vendors.
Settlement and payout. After commission is deducted, the seller's share has to reach them on a defined schedule. Platforms commonly settle marketplace payouts through Stripe Connect or a similar provider that supports splitting funds between operator and seller.
What to look for when evaluating a commission engine
When comparing platforms, the commission demo is where flexibility becomes concrete. Ask to see it, not just hear about it.
Can the platform set rates per category and per seller, not just one global rate? Can rules layer - a per-seller override on top of a category rate? Does commission apply correctly on a multi-vendor order that splits across sellers? And is settlement automated through a payout provider, or does someone reconcile it by hand?
If the commission logic can't be configured without a developer editing code for every rate change, it will not keep up with how you actually run the marketplace.
Mercur
Mercur is an enterprise-grade Open Core marketplace platform - zero license fees, zero GMV fees, full code ownership.
Its commission engine ships with flexible rules out-of-the-box: rates per category and per seller, applied correctly across split orders, with seller payouts settled through Stripe Connect. 80% of marketplace functionality is ready on day one, and because Mercur is Open Core, you can extend the commission logic - tiered rules, custom conditions, your own rate card - without waiting on a vendor's roadmap.
This is the commission flexibility shown in enterprise evaluations against SaaS platforms. Mercur is deployed across 30+ enterprise commerce projects with $6B+ in client trade volume. See Mercur features and the marketplace software comparison.
Frequently asked questions
What is a marketplace commission structure?
It's the set of rules that decide how much the operator takes from each transaction - whether a flat rate, rates that vary by category or seller, or tiers that change with volume - and how that commission is calculated and settled.
What is the difference between flat and tiered commission?
Flat commission charges the same percentage on every transaction. Tiered commission changes the rate with volume - a seller pays a lower percentage above a sales threshold - which rewards growth and gives high-volume sellers a reason to stay.
Can different sellers have different commission rates?
Yes, on a platform with a capable commission engine. Per-seller rates let you offer preferential terms to strategic or high-volume sellers, or introductory rates to new ones, on top of category-level defaults.
How are marketplace commissions paid out?
The commission is deducted from each sale and the seller's remaining share is paid out on a schedule, commonly through a provider like Stripe Connect that supports splitting a single payment between the operator and the seller.
