Variable Custom Expenses Ad Spend
The marketing money that scales with trade but never lands in an ad account.
What it means
Variable Custom Expenses Ad Spend is the part of Variable Custom ExpensesVariable Custom ExpensesSee the full entry. you marked as Ad Spend — rate-based marketing costs that no platform bills you for. An affiliate commission on sales, an agency charging a share of ad spend, a per-order referral fee. It's a subset rather than an addition: everything in here is also inside Variable Custom Expenses, and everything else sits in Variable Custom Expenses excl. Ad SpendVariable Custom Expenses excl. Ad SpendSee the full entry.. It feeds True Ad SpendTrue Ad SpendAd Spend including the custom expenses ad spend configurations.
Show the math
Formula and a worked example
Marked as Ad Spend is a flag on each custom expense. It decides whether the app treats that cost as marketing or as a cost of trading — nothing else about the entry changes.
Variable means the amount comes from a rate: a percentage of sales or ad spend, or an amount per order. It moves with the month whether or not you touch it.
Worked example. March brings €120,000 of Total Sales, 1,500 orders and €20,000 of ad spend. Two rate-based entries are marked as Ad Spend: an affiliate programme at 3% of sales (€3,600) and an agency at 8% of ad spend (€1,600). Variable Custom Expenses Ad Spend = €5,200. The €2 per-order pick fee is trading, not marketing, so it stays out.
That €5,200 adds 26% on top of the €20,000 the platforms billed — and not one euro of it bought a click. It's the difference between what your ad accounts say marketing cost and what your bank says.
It answers the question
How much of my marketing bill scales with the business rather than with my bidding? This line rises when sales or spend rise, whatever you do inside the ad accounts, and pausing a campaign doesn't touch it.
Why it matters
It's the part of marketing you can't fix by turning something off. An affiliate rate is charged on sales you've already made; an agency percentage is charged on spend you've already committed. Both bills arrive after the decision that caused them.
It also sets how far your reported spend drifts from your real one, and it drifts most in a strong month. Scale the account and this grows with it — quietly, at a rate someone agreed to once.
What good looks like
There's no standard euro amount. Two checks are worth doing. First, is every rate-based marketing arrangement in here — affiliates, percentage retainers, referral fees? A store paying an agency on a percentage and reading zero has an entry that's missing or unmarked. Second, is it growing no faster than the sales or spend it's charged on? A rate can only outgrow its own metric if somebody changed the rate.
Then read it as a share of the metric it's billed on. An affiliate programme at 3% of sales is a decision you can judge; €3,600 in isolation is not.
How to improve it
| Lever | What you do | Expect | How long | Watch out for |
|---|---|---|---|---|
| Fast Mark what's actually marketing | Go through the rate-based entries on Cost Settings and flag the ones that exist to win sales | This line rises to the real figure | 1 day | True Ad Spend and True NCPA both get worse the day you fix it. The marketing didn't change — you were reading a number that left part of it out. |
| Fast Cap the percentage | Negotiate a ceiling above a volume threshold so the rate stops compounding on a strong month | The line flattens once you pass the cap | 1 month | A cap usually buys the supplier a higher base rate, so every quiet month costs more than it used to. |
| Slow Swap the percentage for a flat fee | Move an affiliate or agency rate onto a fixed monthly amount | Strong months stop getting more expensive | 1 quarter | Slow months stop getting cheaper, and a fixed marketing fee spread over fewer new customers pushes True NCPA up exactly when you can least afford it. |
| Slow Pay on the metric you actually want | Move a rate charged on ad spend onto orders or sales instead | The cost tracks results rather than budget | 1 quarter | A supplier optimises for whatever they're paid on. A rate on spend rewards spending; a rate on sales rewards discounting. Pick the one whose failure mode you can live with. |
Every lever costs something somewhere. The last column is the one to read twice.
Read it with
Marketing that isn't billed by a platform still has to move with the media it supports. Reading the two together is what shows you when it doesn't.
Check the entries
A rate charged on spend or sales should rise when the media does. A fall usually means an entry ended, or a new arrangement was never entered at all.
Moving together
Both rose, which is exactly what a rate does. The question isn't whether this moved — it's whether the whole marketing bill bought more first-time buyers.
Falling together
You cut media and the rate-based marketing shrank with it. This is why variable arrangements are worth having — the whole bill moved, not part of it.
The bill grew where you weren't looking
You spent less on media and your marketing bill still went up. Usually a sales-based rate meeting a strong month, or an entry added mid-period that nobody connected to the numbers.
Custom Expenses Ad Spend is this plus the fixed marketing entries. The split tells you how exposed your marketing budget is to a slow month: mostly variable and the bill falls with the sales, mostly fixed and it doesn't. Same total, completely different behaviour in January.
The two halves add up to Variable Custom Expenses exactly, so the split is the whole story. If the total holds while this half grows, nothing got more expensive — money moved from serving orders to winning them, and the only place that shows is the pair.
Common misreads
It's zero when nothing rate-based has been marked as Ad Spend. Affiliate commissions and percentage retainers are the two that go missing most often, and both are marketing by any definition you'd use out loud.
Those are two views of the same euro, not two euros. One groups your costs by where they came from, the other groups them by what they were for. Ad Spend itself never includes this.
The rate almost certainly didn't change. It's charged on sales or ad spend, and those did. Check the metric behind the entry before you reopen the contract.
Also called
Variable marketing spend · off-platform ad spend · commission-based marketing cost · affiliate and agency spend
See yoursYour Variable Custom Expenses Ad Spend for the period, and how much of True Ad Spend it accounts for.
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