% Fixed Custom Expenses
How much of every sale goes to the costs that stay the same whether you sell or not.
What it means
% Fixed Custom Expenses is the share of Total SalesTotal SalesYour true top line and the anchor for every efficiency metric. taken by the fixed entries on Cost Settings — rent, payroll, software, an agency retainer. Fixed means a set amount for a period, not a rate that follows sales. Percentage-based and per-order entries sit in % Variable Custom Expenses% Variable Custom ExpensesSee the full entry. instead, and stock, postage and card fees each have their own line.
Fixed entries flagged as Ad Spend are counted here too, alongside the ones that aren't.
Show the math
Formula and a worked example
Fixed Custom Expenses is every fixed entry that was live during the dates you picked. Each one carries a daily cost, and the app charges the days that overlap your range — so a 7-day view holds 7 days of the rent, not the month's invoice.
Total Sales is Gross Sales plus shipping and tax, less discounts and refunds.
Worked example. Your fixed entries add up to €400 a day. March has 31 days, so the app charges €12,400 against €155,000 of Total Sales. % Fixed Custom Expenses = 12,400 ÷ 155,000 = 8%.
April is quiet and not one entry changes. 30 days bills €12,000, Total Sales come in at €100,000, and the same cost base now reads 12%. Nobody overspent — the shop got smaller underneath a bill that couldn't.
The number splits cleanly in two. The flagged share and the unflagged share are measured against the same Total Sales, so % Fixed Custom Expenses Ad Spend plus % Fixed Custom Expenses excl. Ad Spend always adds back to this figure.
It answers the question
Can the sales you make carry the costs you can't switch off? Ad budget goes to zero on a Monday if it has to. A lease, a payroll and a 12-month software contract do not.
Why it matters
This is the part of your cost base that doesn't negotiate with a bad month. It sets the floor your sales have to clear before anything reaches Net ProfitNet ProfitThe bottom line you take home., and it climbs hardest exactly when you can least afford it.
It also tells you what kind of business you've built. Two shops on identical margins behave completely differently in a slow quarter if one carries its overhead as fixed commitments and the other buys it by the order.
What good looks like
The app publishes no bands for this one, and no single share is right for every store — a shop with its own warehouse and a shop on a per-order fulfilment deal should sit nowhere near each other.
Judge it two ways. Against your own trend, same season on both sides, so a 28-day month isn't compared to a 31-day one. And against the split with variable: the more of your cost base that's fixed, the more headroom you need above it. Read it beside Contribution MarginContribution MarginProfit left after variable costs to fund the business.30% or more is healthy, which is what has to cover this before any profit exists.
How to improve it
| Lever | What you do | Expect | How long | Watch out for |
|---|---|---|---|---|
| Fast End what has already stopped | Put an end date on fixed entries for tools, spaces or contracts you no longer use | The daily charge stops from that date | Same week | It changes nothing about past periods, and an entry ended earlier than the contract actually ran understates your costs and flatters Net Profit. |
| Fast Cancel software nobody opens | Audit the recurring app and tool entries against who actually logs in | The daily rate falls | 1–2 weeks | Some of those tools hold a flow, a feed or a checkout step together. One wrong cancellation costs more revenue than the fees ever saved. |
| Slow Turn a fixed cost into a variable one | Move an agency retainer to a share of sales, or warehousing to a per-order rate | This share falls; slow months hurt less | 1 quarter | The cost doesn't disappear, it moves to % Variable Custom Expenses. Strong months now cost more, and across a growing year the total can beat the retainer you left. |
| Slow Grow into the base you already pay for | Add sales without adding people, space or contracts | Falls with every point of growth, no cuts required | 1–2 quarters | Growth bought with ads doesn't help evenly — this improves while the acquisition cost lands in a different line, so Net Profit can stay flat while this looks better. |
Every lever costs something somewhere. The last column is the one to read twice.
Read it with
A percentage moves when either half moves. Reading it against sales is what tells you which one did.
Growing past the base
The rent, the payroll and the contracts didn't move and the shop did. Every point this falls is margin you didn't have to negotiate for.
Buying capacity
You added fixed commitments to grow, and slightly faster than the growth arrived. Reasonable in a quarter you planned. A pattern if it repeats.
Trimmed to fit
Fixed cost came out faster than sales fell, so the shop stayed in proportion through a quiet month. Controlled, not comfortable.
The floor is too high
Nothing was overspent. The sales weren't there, and fixed costs don't shrink on their own — which is how one slow month becomes a loss.
The euro total flat while the share climbs tells you sales fell rather than costs rising — a demand problem, not a spending one. The two point at completely different fixes, and the percentage alone can't tell you which you have.
The wider number covers fixed and variable together. When the two move apart, the mix of your cost base is changing: this one rising faster means more of your overhead has become a commitment, and a slow quarter will now cost you more than the last one did.
Common misreads
Total Sales sit in the denominator. A cost base that didn't move at all reads higher in a slow month. Check the euro total next to it before you go looking for a culprit.
Fixed entries are charged by the day, so a week holds a week of them. What changes with the range is the euro figure, not the share — which is the whole point of reading this column instead of the amount.
It covers what has been entered on Cost Settings and marked as a fixed entry. A store reading 3% has usually entered its software and forgotten its payroll. Check the list before you enjoy the number.
Also called
Fixed cost ratio · fixed overhead as a share of sales · fixed cost percentage
See yoursYour % Fixed Custom Expenses for the period, next to the euro total and the variable side of the same cost base.
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