How to know your break-even revenue this month

If there is one number every UK SME owner should know at the start of each month, it is break-even revenue — the exact level of sales the business needs to cover all its costs with zero profit or loss. Below it, the business is losing money. Above it, everything extra is margin.

And yet the number of small business owners who can tell you their break-even on the spot is small. Most can tell you last month's turnover. Few can tell you what turnover they actually needed.

This guide walks through how to calculate it properly, why the obvious way is usually wrong, and what to do commercially once you know the number.

The simple formula that is almost always misused

Break-even revenue is not complicated. The formula is short:

If your fixed costs are £12,000 a month and your gross margin is 30%, you need £40,000 of revenue just to cover the fixed costs. Anything above £40,000 produces operating profit.

The reason most owners get this wrong is not the formula — it is the two numbers they feed into it. Both fixed costs and gross margin are usually understated.

Why most fixed cost numbers are too low

Ask most SME owners what their monthly fixed costs are and you will get a rent figure, a wages figure, and "a few bits". What they typically miss:

• Employer NI and pension — usually 12-16% on top of gross wages. Not small.
• Software and subscriptions — Xero, Microsoft 365, design tools, CRM, AI tools, hosting. Easy to have £400-£900/month you have forgotten about.
• Professional fees — accountant, bookkeeper, legal advice, insurance brokers. Monthly equivalent of the annual fees.
• Business rates and service charges — often paid annually, so they do not appear in monthly outgoings even though they are accruing.
• Vehicle and equipment lease payments — again, sometimes quarterly or annual.
• The owner's draw/salary — if you are paying yourself less than a market salary to keep the business alive, you are understating cost.

Build a proper list, in a spreadsheet, of every recurring fixed cost converted to a monthly figure. The first time most owners do this, the number is 20-40% higher than they expected.

Why most gross margin numbers are too high

The other half of the equation is gross margin. Most business owners calculate it on selling price minus supplier invoice. That is not your real margin. The real margin is after:

• Freight inbound (ocean, rail, road, courier)
• Duty, VAT costs not reclaimable, and customs clearance
• Insurance and domestic delivery to your stores or customers
• Payment-processor fees (Stripe, PayPal, card terminals — typically 1.5-3% of revenue)
• Marketplace fees (Amazon, Etsy, eBay — 10-15% on top of payment)
• Packaging, returns cost, shrinkage, damaged stock

A UK distributor who thinks their margin is 35% on the supplier invoice will often find it is closer to 27-29% on actual landed, fulfilled, received-cash basis. That difference — six to eight percentage points — changes break-even materially.

A realistic UK SME worked example

Take a small product business. Monthly fixed costs, once properly built up: £18,500. Gross margin, once properly calculated on true landed cost plus payment and fulfilment fees: 28%.

This business needs £66,000 of revenue a month just to stand still. In a 21-trading-day month, that is £3,146 per day. In a 4-week month, £16,517 per week.

That number is the one the owner needs on a post-it note above the desk. Every Monday morning, they should know how last week compared against it.

What good break-even discipline looks like month to month

Once you know the number, use it properly. A few habits that separate the businesses that get stronger each quarter from the ones that drift:

• Weekly check-in. At the end of each week, log revenue and divide break-even by 4.33. If you are below, you know before the end of the month and can act.
• Cost review quarterly. Break-even moves when costs move. The April 2026 step-up in National Living Wage and employer National Insurance will have raised break-even for most SMEs by 3-5%. Recalculate.
• Margin check on every new product line. Adding volume at below-average margin lowers your blended margin and raises break-even.
• Benchmark against capacity. If break-even is 70%+ of your realistic capacity, the business is structurally fragile. Either lift margin or lift capacity.
• Share the number with your team. If the manager responsible for sales does not know the break-even number, they cannot help you beat it.

What to do when revenue is below break-even

Every business has a bad month sometimes. One below-break-even month is cashflow pressure, not a crisis. Three in a row is a crisis. Here is the decision ladder:

First, check the calculation is still right.

Fixed costs change. Margin drifts. Before you panic, confirm the number. Margin is the most likely thing that has quietly fallen — pricing erosion or rising input costs.

Second, look at contribution, not just revenue.

If gross margin is holding but revenue is short, the fix is demand and pricing. If revenue is holding but margin is down, the fix is cost-side: supplier renegotiation, product mix, pricing discipline.

Third, cut fixed cost if it is a structural miss.

Below break-even for three months in a row is a sign that the cost base is too high for the business's realistic revenue level. That is a fixed-cost problem, not a sales problem. The SMEs that handle this well cut early and decisively; the ones that do not burn through working capital first and are forced to cut anyway, from a weaker position.

Common questions