% Variable Custom Expenses
How much of every euro of sales is promised to costs that scale with the business.
What it means
% Variable Custom Expenses is the share of Total Sales taken by the entries you added on Cost Settings as variable — the ones defined as a rate rather than a fixed bill. A variable entry is set as a percentage of Total Sales, a percentage of ad spend (all channels, Meta only, or Google only), or an amount per order, so what it charges follows the month rather than the calendar.
Rent, payroll and software subscriptions aren't in it; those are fixed entries and sit in their own column. Stock, postage and payment fees aren't either — COGSCOGSKeep it synced from Shopify, or every profit number is guesswork., Shipping CostShipping CostShipping Cost calculated as per settings and Gateway CostGateway CostSee the full entry. each have their own line.
Show the math
Formula and a worked example
Variable Custom Expenses is every variable entry from Cost Settings, resolved for the period: a percentage entry is applied to its own base, a per-order entry is multiplied by your order count, and an entry that only covers part of the range is prorated by the days it covers.
Total Sales is everything you took in, tax and delivery charges included.
Worked example. March: €120,000 of Total Sales, 1,500 orders, €30,000 of ad spend. A 6% sales commission charges €7,200. A €2 pick-and-pack fee charges €3,000. A 10% agency fee on ad spend charges €3,000. Variable Custom Expenses = €13,200, so the column reads 13,200 ÷ 120,000 = 11%.
April is quieter: €90,000 of sales, 1,100 orders, ad spend held at €30,000. Commission falls to €5,400, pick-and-pack to €2,200, and the agency fee stays at €3,000 because its base didn't move. The bill drops to €10,600 — and the column rises to 10,600 ÷ 90,000 = 11.8%.
You paid less and it costs you more per euro. That gap is the entire reason to read this column rather than the euro total.
It answers the question
How much of each euro of sales is spoken for before you count anything fixed? This is the part of the cost base that shrinks in a bad month — and the part that never stops growing in a good one.
Why it matters
The split between fixed and variable is what decides whether a quiet quarter is uncomfortable or fatal. Fixed cost is the dangerous half when sales fall. Variable cost is dangerous in the other direction: it's a permanent charge on every sale, so it sets a ceiling on the margin the business can ever reach, no matter how big it gets. Growth doesn't dilute it.
It also lands where you can see it. Custom expenses are taken out in Net ProfitNet ProfitThe bottom line you take home. and nowhere above it, so a variable cost base that's quietly climbing leaves Gross MarginGross MarginProfit after product cost; the ceiling on what you can spend to grow.60% or more is healthy looking completely healthy while the bottom line thins.
What good looks like
There are no published bands for this column, and the level matters less than the steadiness. If your variable entries are mostly percentages of sales, this should sit almost still month after month — that's a rate doing what a rate should. Movement is the signal, not the number.
Compare it with the rates you actually agreed. If your sales-based entries add up to 6% and this reads 11%, the gap is the per-order and ad-based entries, and both are worth understanding. The app does grade the combined column, % Custom Expenses% Custom ExpensesHow much of sales your extra costs consume.Under 12% is healthy, at under 12% healthy and over 30% needing work; this is one component of that total, so there's no separate band to hit here.
How to improve it
| Lever | What you do | Expect | How long | Watch out for |
|---|---|---|---|---|
| Fast Re-cut the rates themselves | Renegotiate the commission and fee percentages behind the largest entries | A sales-based rate cut moves this column by exactly the points you cut | 2–4 weeks | Rates buy effort. A commission cut usually costs you the people doing the selling, and an agency on a lower percentage gives you fewer hours. |
| Fast Check every entry is charging on the right base | Open Cost Settings and confirm each rate points at sales, ad spend or orders as it should | The number becomes true — sometimes worse | Same week | A per-order fee entered as a percentage of sales, or a Meta fee charged against blended spend, has been wrong in both directions. Net Profit moves when you fix it. |
| Slow Raise the basket so per-order fees spread | Add thresholds or bundles so a €2 fee sits on a bigger order | This column falls with no rate changing at all | 1 quarter | Baskets built with discounts are paid for in margin. Watch % Product Discounts and AOV together before you count the saving. |
| Slow Swap a rate for a flat fee | Move a percentage-based partner onto a retainer | This column falls, % Fixed Custom Expenses rises to meet it | 1 quarter | You gave up the protection you were paying for. A flat fee doesn't shrink when the month does, which is exactly what a variable rate was buying. |
Every lever costs something somewhere. The last column is the one to read twice.
Read it with
The share and the sales underneath it move for different reasons. Reading them together tells you whether a rise came from spending or from a smaller month.
Costs growing faster than sales
You grew and each euro got more expensive. Usually an entry charged on ad spend while the spend outran the sales it produced.
Growing into the rates
Sales outgrew the per-order and ad-based pieces. Every point this falls lands on Net Profit without one negotiation.
The bill fell and the share didn't
A quiet month with fees that don't follow sales. Nothing was overspent — the entries charged on ad spend and on orders kept their own bases.
Both easing
Sales fell and the variable base fell faster, usually because spend was cut with them. Controlled, not comfortable.
The two halves of the same cost base, on the same denominator, adding up to % Custom Expenses. A shop that's mostly fixed breaks in a quiet quarter. A shop that's mostly variable survives every quarter and never earns the margin that scale is supposed to bring. Neither number tells you which shop you are.
This is one of the deductions inside Net Profit, and it appears in no margin above it. When Gross Margin holds steady and Net Profit Margin slips, this column and the fixed one beside it are the first place to look — the cost is real and it's invisible two rows up.
Common misreads
Total Sales is the denominator. A completely unchanged set of rates against a smaller month pushes this up with nothing renegotiated anywhere. Read Variable Custom Expenses in euros beside it before you go hunting.
Only the entries based on sales do. A fee charged on ad spend follows your budget, and a per-order fee follows your order count. Both can hold — or rise — through a month when revenue drops.
More often it means nothing has been entered on Cost Settings yet. An empty variable list reads as free, and every profit figure below it is flattering you by the same amount.
Also called
Variable cost ratio · variable overhead share · variable expenses as a share of sales
See yoursYour variable share for the period, beside the fixed share, the euro totals behind both, and the entries producing them on Cost Settings.
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