The Only Metrics Early-Stage D2C Brands Should Track

If you’re a D2C founder doing under £10 million a year, here’s something you need to hear: stop overcomplicating your reporting.

The 11 metrics below will tell you everything you need to know. But “track 11 things” isn’t the same as “the only metrics you need”, so let’s be honest about the hierarchy first.

If you only track three, track these:

1. Blended CAC – what it actually costs you to win a customer across all channels.
2. LTV:CAC ratio – whether each customer is worth more than you paid to acquire them.
3. CAC payback period – how long your cash is tied up before that customer repays their acquisition cost.

Those three answer the only question that matters at this stage: are you buying customers profitably, and can your cash survive the wait? The other eight sharpen the picture, but if you’re drowning, start there.

For a scannable summary of all 11 – formula, benchmark and how often to check each one – jump to the at-a-glance table.

1. How much does it cost to acquire a customer?

Blended CAC (Customer Acquisition Cost)

This is your starting point. Don’t obsess over platform-reported CPA – it’s often misleading, especially with channel overlap and tracking issues. Look at blended CAC instead: total marketing spend divided by new customers acquired in that period. That gives you a true, cross-channel view of what it actually costs to grow.

Formula: Blended CAC = total marketing spend ÷ new customers acquired (same period).

2. How quickly do you recover that cost?

CAC Payback Period

If you’re acquiring customers for £40, but they don’t pay that back for 9 months, you’ve got a cash flow problem. A short payback window means you’re building a sustainable machine. This is especially crucial if you’re bootstrapped or lightly funded.

Formula: CAC payback (months) = CAC ÷ (monthly gross profit per customer).

What good looks like: under 90 days is excellent; 90–180 days is typical for a healthy DTC brand; 12 months is the outer limit before your cash gets uncomfortable. High-frequency, high-margin categories (beauty, food and drink, pet) should aim for the shorter end.

3. Do your customers come back?

Repeat Purchase Rate & Time Between Orders

Knowing how many customers come back – and how quickly – is everything for forecasting growth. A solid repeat rate with a short interval between first and second orders is a healthy signal. It also means you can afford to be more aggressive on acquisition, because lifetime value will carry the load.

Formula: Repeat purchase rate = customers with more than one order ÷ total customers (in a period).

What good looks like: roughly 25–30% for an average DTC brand, 35–45% for consumables and replenishables, and 15–20% for durables (things people buy once and rarely again). If yours is well below the band for your category, that’s usually a retention or product problem, not an acquisition one. We unpack why this number misleads so many brands in Returning Customer Rate: Why It’s Not What You Think.

4. How profitable is each sale – really?

LTV (Customer Lifetime Value)

LTV tells you how much margin you can expect over the customer journey. Break it down by product, customer type, or category if possible. Understanding your contribution margin by segment helps you prioritise where to focus your budget. Not all customers are created equal.

Formula: LTV = AOV × purchase frequency (orders per year) × gross margin × customer lifespan (years).

What good looks like: there’s no universal target – LTV only means something relative to what you paid to acquire the customer, which is exactly why the next metric exists. Use margin-based LTV, not revenue, so you’re not flattered by top-line numbers.

4b. Is each customer worth more than you paid for them?

LTV:CAC Ratio

This is the single most important number in DTC unit economics, and it’s the one the “only metrics” promise really hinges on. It compares the lifetime margin of a customer against what it cost to acquire them.

Formula: LTV:CAC = customer lifetime value ÷ blended CAC.

What good looks like: 3:1 is the widely cited healthy minimum – three pounds of lifetime margin for every pound of acquisition cost. Below that and you’re not leaving enough room for overheads and reinvestment; far above it (say 5:1 or more) and you may actually be under-investing in growth. Most healthy sub-£10M brands sit in the 3:1 to 4:1 range. Read the ratio alongside CAC payback: two brands can share a 3:1 ratio but have very different cash profiles depending on how quickly that margin comes back. For a fuller breakdown of how CAC, LTV and payback fit together, see Mastering Unit Economics in Paid Ads.

5. Is your marketing spend pulling its weight?

ROMI (Return on Marketing Investment) or MER (Marketing Efficiency Ratio)

Whether you use ROMI or MER, what you’re really looking at is return on ad spend from a business-wide lens. MER is a great macro metric for founders who want to see the forest, not just the trees, and it dodges most of the attribution mess that trips up platform-reported ROAS.

Formula: MER = total revenue ÷ total marketing spend.

What good looks like: it scales with your stage and category. £1M–£5M brands often run a blended MER of around 1.5–2.5, £5M–£10M brands nearer 2.5–3.5. If you’re past launch and sitting below 2, you’re either spending too hard or your funnel is leaking conversions.

6. How fast are you turning inventory into cash?

Inventory Sell-Through Rate

There’s no point scaling up ad spend if you’re sitting on dead stock. A healthy sell-through rate means your products are moving at the pace you’re forecasting. If it’s lagging, you’re tying up capital that could be fuelling growth elsewhere.

Formula: Sell-through rate = units sold ÷ units received × 100 (over a set period).

What good looks like: roughly 70–80% per period for general retail, with apparel around 65–85% and beauty and consumables 75–90%. Below 40% per period is a warning sign of overstock or a weak product. Evergreen core lines can sit lower than seasonal ranges and still be healthy, so judge each line against its own plan rather than a single blanket target.

7. How long can your business run before the cash runs out?

Cash Runway

Cash runway tells you how many days or months you’ve got left at current burn. It’s not the most glamorous metric, but it’s one of the most important. Especially in uncertain climates, knowing your runway buys you time to make smarter decisions.

Formula: Cash runway (months) = current cash balance ÷ average monthly net burn.

8. What’s your financial forecast for the next 90-120 days?

Cash Burn Rate & Revenue Projection

These short-term projections are your early warning system. If you’re scaling fast, but your cash position doesn’t support that growth, you’ll need to adjust. Predict cash burn, and model conservative revenue scenarios to stay ahead of any squeeze.

Formula: Net burn rate = cash out − cash in (per month). Pair it with a rolling 90–120 day revenue projection.

9. What happens if things don’t go to plan?

Scenario Planning

Don’t just plan for growth – plan for turbulence. If your paid performance drops, or your top SKU goes out of stock, do you know how that affects cash flow and headcount? Running “what if” scenarios gives you confidence under pressure.

10. Are you holding too much product?

Inventory Overstock

Overstock kills cash flow. It’s often a result of over-forecasting based on optimistic growth plans. Review your overstock position monthly. If you’re holding more than 30-60 days’ worth of slower-moving items, it’s time to rethink your supply chain assumptions.

11. How do these numbers compare to last year or last quarter?

Period-Over-Period Comparison

Growth isn’t just about topline numbers. It’s about progress. Always track how your key metrics are trending over time – CAC, LTV, payback period, etc. Context gives meaning. Improvement over last quarter is the goal, even if you’re not hitting every target.

The metrics at a glance

Here’s every metric in one place – the formula, a rough sense of what “good” looks like for a sub-£10M DTC brand, and how often it’s worth checking. Treat the benchmarks as starting points, not gospel; the right target depends on your category and margins.

Metric	Formula	What “good” looks like (sub-£10M DTC)	Review frequency
Blended CAC	Total marketing spend ÷ new customers	Trending down or stable as you scale	Weekly
CAC payback period	CAC ÷ monthly gross profit per customer	< 90 days great, < 12 months the ceiling	Monthly
Repeat purchase rate	Repeat customers ÷ total customers	~25–30% (35–45% consumables, 15–20% durables)	Monthly
LTV	AOV × frequency × gross margin × lifespan	Only meaningful vs CAC (see below)	Quarterly
LTV:CAC ratio	LTV ÷ blended CAC	3:1 minimum, 3–4:1 healthy	Monthly
MER	Total revenue ÷ total marketing spend	~1.5–2.5 (£1–5M), ~2.5–3.5 (£5–10M)	Weekly
Sell-through rate	Units sold ÷ units received × 100	~70–80% per period; < 40% is a red flag	Monthly
Cash runway	Cash balance ÷ monthly net burn	Enough to weather a bad quarter	Monthly
Cash burn & projection	Cash out − cash in; rolling 90–120 day forecast	Burn supported by cash on hand	Monthly
Scenario planning	Modelled “what if” cases	A downside plan you could act on tomorrow	Quarterly
Inventory overstock	Days of slow-moving stock on hand	< 30–60 days of slow movers	Monthly
Period-over-period	This period vs last period/year	Key metrics improving over time	Monthly / Quarterly

How to build this into one simple report

You don’t need a data team or an expensive stack. The point of a sub-£10M report is that one person can maintain it and everyone can read it.

• Pick one home for the numbers. For most brands that’s a single spreadsheet fed by Shopify (or your platform), your ad accounts and your bank feed. If you outgrow that, a lightweight dashboard tool like Shopify’s built-in analytics, Google Looker Studio or a purpose-built DTC tool such as Polar or Triple Whale does the same job with less copy-paste.
• Split it by cadence. Check the fast-moving numbers – MER, blended CAC, spend – weekly. Reconcile the fuller picture – payback, LTV:CAC, sell-through, cash – monthly. Revisit LTV and scenario plans quarterly, since they don’t swing week to week.
• Show the trend, not just the number. A metric on its own means little; the same metric next to last month and last quarter is what tells you whether you’re actually getting better.

Keep it boring and keep it consistent. A report you update every Monday beats a beautiful one you build once and abandon.

Frequently asked questions

What’s the difference between CAC and blended CAC? Platform-reported CAC (or CPA) counts only the customers a single channel claims credit for, which double-counts and over-attributes once channels overlap. Blended CAC divides your total marketing spend by all new customers in the period, giving one honest, cross-channel cost of growth.

Is a higher LTV:CAC ratio always better? No. Below 3:1 you’re not leaving enough margin for overheads and reinvestment, but a very high ratio (5:1 or more) often means you’re under-spending and leaving growth on the table. Most healthy sub-£10M brands sit around 3:1 to 4:1.

How often should I actually look at these? Weekly for the fast movers (MER, blended CAC, spend), monthly for the unit economics and cash picture, and quarterly for LTV and scenario planning. Checking everything daily just adds noise.

Which metrics can I safely ignore early on? Vanity metrics that don’t connect to profit or cash – impressions, follower counts, raw website traffic, and platform ROAS in isolation. They feel like progress without telling you whether you’re building a business.

Rounding Up

If you’re doing under £10M in revenue, you don’t need a CFO-level dashboard. You need a simple, reliable report that answers these questions – and if you only have the bandwidth for three, keep your eyes on blended CAC, LTV:CAC and CAC payback. Get those right and the rest follows.