Measurement
Part of Customer lifetime value formula for UK B2B: how to calculate it
Customer lifetime value formula for UK B2B: how to calculate it
Work out customer lifetime value in pounds for UK B2B accounts: gross margin, churn, VAT treatment and a worked example with the CLV formula.
What to take away
- Customer lifetime value (CLV) is the gross-margin profit one account should produce over its life, not the cash it bills.
- The base formula divides average monthly gross margin per account by the monthly churn rate.
- Work in pounds net of VAT, because output tax collected for HMRC is not your revenue.
- Churn moves CLV far more than price does, so refresh the inputs every month.
- CLV sets the ceiling on what you can sensibly spend to win and keep an account.
Revenue per account is not value
A £40,000 a year account that consumes £25,000 of support and hosting is not your best customer. Revenue reporting cannot see that. CLV starts from gross margin, the money left after direct cost to serve, and spreads it across the expected life of the relationship.
UK B2B contracts help here. Seat counts, renewal dates and onboarding fees are usually known, so the margin figure rests on evidence rather than assumption. That is why CLV models hold up better in business software than in consumer subscriptions.
The formula, step by step
Most definitions, including customer lifetime value on Wikipedia, reduce to margin divided by churn. Three inputs do the work, and a fourth adjusts for contracts that run long.
CLV formula in four steps
- Average monthly gross margin per account
- Monthly churn ratelost accounts divided by opening accounts
- Base CLVmargin divided by churn rate
- Add expansion margin, discount beyond two years
- Average monthly gross margin per accounttake monthly recurring revenue, subtract the direct cost to serve, including hosting and amortised onboarding, then divide by the number of live accounts. Keep every figure net of VAT.
- Monthly churn ratedivide accounts lost during a month by the accounts open at the start of it. A logo leaving counts; a downgrade does not.
- Base CLVdivide monthly gross margin per account by the monthly churn rate. The answer is the margin a typical account is expected to deliver.
- Expansion and discountadd the margin you expect from upsells, then discount future margin if the contract runs beyond two years.
Churn sits in the denominator, so the answer is sensitive to it. A fall from 2% to 1.5% lifts CLV by a third. That is why your customer retention metrics deserve the same monthly review as new bookings.
A worked example in pounds
A UK software business bills £2,000 a month per account, excluding VAT, and serves each account for £700 a month. It opens the month with 200 accounts and loses three.
Worked CLV example in pounds
- £2,000Revenue per account per month, net of VAT
- £700Direct cost to serve per account per month
- £1,300Gross margin per account per month
- £86,667Base CLV at 1.5% monthly churn
| Input | Figure |
|---|---|
| Revenue per account per month, net of VAT | £2,000 |
| Direct cost to serve per account per month | £700 |
| Gross margin per account per month | £1,300 |
| Accounts at the start of the month | 200 |
| Accounts lost during the month | 3 |
| Monthly churn rate | 1.5% |
| Base CLV, £1,300 divided by 1.5% | £86,667 |
That is roughly 67 months of margin, or £15,600 a year per account. The numbers are illustrative. Cut churn to 1% and the same account is worth £130,000, with no price change at all.
A 10% price rise adds £130 a month and lifts CLV to £95,333. Both levers work, but retention compounds. A price rise applies once, churn applies every month.
VAT, currency and data
Work net of VAT throughout. An invoice of £2,400 including VAT at 20% is £2,000 of revenue and £400 of output tax that belongs to HMRC. Once turnover passes the threshold, registering for VAT is compulsory, which changes your invoices but not the CLV calculation.
Multi-year deals priced in dollars or euros add a currency question. Convert at a rate you state in the model notes and keep it consistent, so the CLV trend reflects account behaviour rather than exchange-rate noise.
Churn models also process personal data. If you score named contacts or track usage per user, follow ICO guidance on UK GDPR and record your lawful basis before the model goes live.
Common questions
Does CLV use revenue or gross margin?
Gross margin. Revenue-based CLV flatters accounts that are costly to serve, and those accounts are the ones most likely to leave. Use the margin figure after direct cost to serve.
Which churn rate should a UK B2B team use?
Base the formula on monthly logo churn, and report revenue churn separately so downgrades do not disappear. If churn is above the norm for your segment, fix the causes first: our guide to how to reduce SaaS churn sets out practical steps and benchmarks.
How often should CLV be recalculated?
Monthly, on the same cycle as your retention reporting. Quarterly is workable for smaller teams, but a single bad cohort can distort an annual figure.
Should I discount future margin?
Only when contracts run beyond two years, or when you are comparing accounts with very different deal lengths. A simple annual discount rate, stated in the notes, is enough for most UK B2B decisions.
