Variable Custom Expenses
The half of your running costs that shrinks on its own when the month is quiet.
What it means
Variable Custom Expenses is the euro total of the costs you entered on Cost Settings as a rate rather than an amount — a percentage of Total Sales, of Meta, Google or blended ad spend, or a flat amount per order. The app applies each rate to its metric for the dates you're looking at, so this total moves with trade instead of with the calendar. Fixed Custom ExpensesFixed Custom ExpensesSee the full entry. is the other half; the two together make Custom ExpensesCustom ExpensesSee the full entry..
Show the math
Formula and a worked example
A rate, not an amount. Every entry is either a percentage of a metric — Total Sales, Ads Blended, Ads Meta, Ads Google — or a fixed amount per order.
Applied during the selected period means an entry counts only for the days its start and end dates overlap the range on screen.
Worked example. Two entries are live in March: a €2 per-order pick fee and an agency on 8% of ad spend. The month brings 1,500 orders and €20,000 of ad spend. 1,500 × 2 = €3,000, plus 20,000 × 0.08 = €1,600. Variable Custom Expenses = €4,600.
April is half the size. The same two entries, unchanged, produce roughly half the cost. Nothing was cancelled and nobody negotiated — the rates met a smaller number. That's the entire point of entering a cost this way.
It answers the question
How much of my cost base looks after itself when trade slows? Everything not in this line is fixed, and fixed costs only come down when somebody decides to cut them.
Why it matters
Two shops with identical Custom Expenses behave completely differently in a bad quarter if one of them is mostly variable. This number is what tells you which shop you're running.
The mix is a decision, not an accident. A cost base weighted to variable protects you in a slow month and costs you more in a strong one — which is the right trade depends on how predictable your year is.
What good looks like
There's no standard euro figure; it depends on how much of your operation you rent by the order. Two checks are worth doing. First, completeness: are the per-order fees, marketplace commissions and percentage retainers you actually pay all entered? Second, proportion: how much of Custom Expenses is this, and is that share where you want it before your next slow quarter?
For a size-independent read, % Variable Custom Expenses% Variable Custom ExpensesSee the full entry. puts the same total against Total Sales, which is the comparison that survives a growing business.
How to improve it
| Lever | What you do | Expect | How long | Watch out for |
|---|---|---|---|---|
| Fast Check the rates against the invoices | Compare every percentage and per-order amount on Cost Settings to what the supplier actually bills | The total lands on the real number | 1 day | Corrections usually go upward, and every profit line beneath this one gets worse the moment you fix it. |
| Fast Renegotiate the per-order fee | Take pick, pack and handling rates back to your fulfilment partner with your current volume | Falls with every order you ship | 1 month | Cheaper handling is usually slower or less careful handling. You'd see it in refunds and complaints before you see the saving here. |
| Slow Move a percentage onto a flat fee | Convert a sales-based agency or partner rate into a fixed monthly amount | Strong months stop getting more expensive | 1 quarter | Quiet months stop getting cheaper. You've traded a cushion for a ceiling, and the cushion is what carries you through a bad January. |
| Slow Take the rate off ad spend | Move an agency billed as a share of spend onto sales, orders or a flat fee | This line stops rising every time you scale a campaign | 1 quarter | A supplier optimises for whatever they're paid on. Off a spend-based rate, they have less reason to grow the account — and more reason to protect the metric you moved them to. |
Every lever costs something somewhere. The last column is the one to read twice.
Read it with
A variable cost is meant to move. Reading it against the trade it's charged on is the only way to tell correct behaviour from a change nobody noticed.
Check the end dates
A rate-based cost that falls while sales rise is unusual. Nine times out of ten an entry's end date passed and the cost is still real — the profit underneath is overstated until somebody re-enters it.
Behaving correctly
Bigger month, bigger rate-based bill. This is what a variable entry is supposed to do. It's only a problem if the cost grew faster than the sales paying for it.
The cushion working
Trade slowed and this part of the cost base slowed with it, without anyone making a decision. Whatever pressure the month created is coming from elsewhere.
Rates moved, not volume
Costs rose on falling sales, which a rate alone can't do. Either a new entry started, a rate was raised, or an edit reached back into the period you're reading.
The split between them is how your business handles a bad month, and neither number shows it alone. A cost base that's 70% fixed needs decisions and notice periods to shrink; one that's 70% variable falls away with the sales. Read the two before you sign anything with a twelve-month term.
The second is a subset of the first, so the gap between them is your non-marketing rate-based cost. If the total holds while the marketing half grows, you haven't spent more — you've moved money from serving orders to winning them, which is a strategy change nobody announced.
Common misreads
The rates are usually unchanged and the metric they're charged on grew. Check Total Sales, orders and ad spend for the period before you ring anyone.
A €2 per-order fee across 12,000 orders a year is €24,000 — more than most shops pay in rent. The size is the rate times the metric, and the word tells you nothing about either.
Entries carry start and end dates, and the app applies them to whatever range you look at. Editing one reshapes past periods too, which is why the app warns you before you save.
Also called
Variable costs · variable overheads · rate-based expenses · per-order costs
See yoursYour Variable Custom Expenses for the period, and the entries producing them on Cost Settings.
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