Ask most founders what their burn rate is, and they’ll give you a number. Ask them what their burn multiple is, and you’ll often get a pause.

That pause is worth paying attention to – because burn multiple is one of the metrics that experienced investors are increasingly focused on, and the gap between founders who understand it and those who don’t shows up quickly in funding conversations. Here’s what it is, why it matters, and what a strong result looks like.

What Is Burn Rate?

Burn rate is the simpler of the two metrics. It’s the amount of net cash your startup is spending each month – typically calculated as your total cash out minus your total cash in. If you’re spending £120,000 a month and bringing in £40,000, your net burn is £80,000.

Burn rate is useful because it tells you how long your runway is. Divide your available cash by your monthly net burn and you know how many months you have before you need to either raise again or reach breakeven. It’s a critical number to track – but it doesn’t tell you whether that spending is actually working.

What Is Burn Multiple?

Burn multiple closes that gap. The formula is straightforward:

Burn Multiple = Net Burn ÷ Net New ARR

In plain terms: for every pound of new annual recurring revenue you’re generating, how many pounds are you burning to get it?

If your startup burned £500,000 last quarter and added £250,000 in net new ARR, your burn multiple is 2x. You’re spending two pounds for every pound of new revenue you’re adding.

The lower the number, the more efficiently you’re growing. A burn multiple of 1x or below is considered excellent. Between 1x and 1.5x is strong. Creeping above 2x starts to raise questions, and anything above 3x is a signal that your growth engine isn’t as efficient as it needs to be.

Why Investors Care About It More Than Burn Rate Alone

Here’s the core issue with burn rate as a standalone metric: it tells you nothing about what the spending is producing. A startup burning £200,000 a month might be doing so brilliantly if it’s generating proportionate revenue growth. That same burn rate with flat ARR is a very different story.

Burn multiple gives investors a single number that captures both sides of the equation – how aggressively you’re spending and how much return you’re getting on that spend. It’s a direct measure of capital efficiency, which is increasingly what investors prioritise as the fundraising environment has tightened.

This shift in emphasis has been notable over the last couple of years. In an era of cheap capital, investors were more tolerant of high burn in exchange for growth at any cost. That calculus has changed. Capital efficiency is now a differentiator, and burn multiple is one of the clearest ways to demonstrate it.

What Affects Your Burn Multiple?

Several things can push your burn multiple up or down. Sales and marketing efficiency is often the biggest driver – if your CAC is high relative to the revenue you’re closing, that inflates your multiple. Churn plays a role too, because net new ARR accounts for the revenue you’re losing as well as the revenue you’re adding. A business with high gross additions but significant churn will have a worse burn multiple than its headline growth figures suggest.

Headcount is another major variable. Hiring ahead of revenue – which is often necessary for product-led businesses – can temporarily inflate your burn multiple before the revenue catch-up happens. In those cases, being able to explain the dynamic clearly to investors matters as much as the number itself.

How to Talk About It With Investors

If your burn multiple is strong, lead with it. It’s a concise, credible signal of capital efficiency that resonates with experienced investors.

If it’s not where you’d like it to be, don’t hide it – explain it. Show the trend, show what’s driving it, and show the path to improvement. Investors fund founders who understand their own business and can navigate challenges honestly. What they don’t fund is founders who present metrics without understanding what’s behind them.

The best thing you can do before any investor conversation is make sure you know your burn multiple, know what’s driving it, and know what it should look like six and twelve months from now.

Disclaimer: This article is general in nature and does not constitute financial advice. Metrics and benchmarks vary by business model and stage – speak to a qualified advisor about what matters most for your situation.