What is Expansion MRR?
Formula
Expansion MRR = Σ (MRR increases on customers active at period start)
- MRR increases
- Upgrades to a higher plan, added seats or units, new recurring add-ons, contractual price rises, and coupon expiries
- customers active at period start
- Accounts already paying at the beginning of the period — new customers contribute New MRR, not expansion
Worked example
One month of upward movement on an existing customer base.
| Step | Value |
|---|---|
| 114 accounts upgrading plan tier | $3,100 |
| 2Seat additions across 41 accounts | $2,250 |
| 3New recurring add-ons | $980 |
| 4Coupon expiries returning accounts to list price | $310 |
| 5Expansion MRR | $6,640 |
| 6New MRR from customers acquired this month | $8,400 |
| 7Expansion as a share of gross new revenue | 44% |
Result
Expansion MRR is $6,640. Nearly half of the month's gross revenue growth came from customers the business already had, which is the component that costs almost nothing to acquire.
The cheapest revenue a subscription business has
Expansion revenue carries close to no acquisition cost. There is no ad spend, no sales cycle against a stranger, no onboarding from zero — the customer already exists, already trusts the product, and is buying more of it. That is why a business with strong expansion can run a higher CAC than its peers and still be healthier, and why net revenue retention above 100% is treated as the single strongest signal in SaaS: it means the installed base grows without any new customers at all.
It also compounds against churn in a way new business does not. New customers replace lost revenue once. Expansion replaces it continuously, from a base that keeps getting larger.
What counts, and what only looks like it
Expansion is an increase in recurring revenue on an account that was already paying at the start of the period: a plan upgrade, added seats, a new recurring add-on, a contractual uplift, or a discount expiring back to list price. Three things routinely get miscounted.
- Reactivations — a previously cancelled customer returning is not expansion. It is its own movement, and folding it into expansion overstates how much your live base is growing.
- New customers who upgrade in their first month — the whole first-month value is New MRR. Splitting it makes acquisition look weaker and expansion stronger than either is.
- One-off charges and usage overage — not recurring, therefore not MRR, therefore not expansion, however welcome the cash.
Gross expansion is not net expansion
Expansion MRR alone is a one-sided number. The same month that produced $6,640 of upgrades may have produced $4,000 of contraction from downgrades and seat reductions, and the base only grew by the difference. Report the two together, always. A business showing large expansion and equally large contraction has volatile accounts rather than growing ones, and the single figure will not reveal it.
What actually drives it
Expansion is a pricing-model property before it is a customer-success one. A flat per-account price gives customers no way to spend more without changing plan, so expansion depends entirely on tier upgrades. A price that tracks a value metric — seats, usage volume, workspaces, transactions — lets revenue grow with the customer automatically, and that structural choice explains most of the difference between companies with 95% and 120% net revenue retention.
The second driver is where growth is even possible. If most of your base is already on the top tier, expansion has a ceiling regardless of how well anyone sells. Segmenting expansion by plan tier tells you whether the ceiling is close, and it is the fastest way to find out whether the answer is more customer success or a different packaging.
Measuring it honestly
Compute expansion from per-customer, per-day plan transitions rather than by differencing account totals month to month — differencing hides an account that upgraded and downgraded in the same period, reporting a quiet month where two real movements happened. Track expansion as a share of gross new revenue, and by cohort: older cohorts should expand more, and if they do not, either the product stops growing with the customer or nobody is asking.
Where Expansion MRR goes wrong
- Counting reactivated customers as expansion. Winning back a cancelled account and growing a live one are different motions with different costs, and merging them overstates how much the existing base is growing.
- Splitting a new customer's first-month upgrade between new and expansion. The whole first-month value belongs to New MRR; splitting it understates acquisition and inflates expansion in the same stroke.
- Reporting expansion without contraction. Gross expansion of $6,640 against $6,000 of downgrades is a base that barely moved, and only the pair of figures shows it.
- Differencing monthly account totals instead of tracking plan transitions. An account that upgraded on the 3rd and downgraded on the 27th reports as flat, and two real movements disappear from the ledger.
- Including one-off charges or usage overage. Neither recurs, so neither is MRR, and folding them in makes the run rate move for reasons that will not repeat next month.
Typical ranges
The commonly cited convention is that best-in-class B2B SaaS businesses generate a substantial share of new revenue from the existing base — enough to push net revenue retention above 100%, and in strong cases well beyond it. Consumer and self-serve products typically sit far lower, because a single-seat product with flat pricing has no structural route to expansion. Compare expansion as a share of gross new revenue against your own trailing quarters rather than against a cross-segment figure.
Related
Metrics that move with this one
No metric explains a business on its own. These are the figures that qualify, offset or explain Expansion MRR.
Contraction MRR
Contraction MRR is recurring revenue lost from customers who stayed but now pay less — downgrades to a cheaper plan, removed seats, dropped add-ons and newly applied discounts. It is distinct from churned MRR, which comes from customers who left entirely, and keeping the two separate matters because a shrinking account is a retained relationship with a product or pricing problem, while a churned one is gone.
Learn moreNet New MRR
Net new MRR is the change in monthly recurring revenue over a period, calculated as new plus expansion plus reactivation MRR, minus contraction and churned MRR. It is the single figure that reconciles opening MRR to closing MRR, and its value comes less from the total than from the five components underneath it, which distinguish a business growing from acquisition, from expansion, or merely replacing what it loses.
Learn moreNet Revenue Retention (NRR)
Net revenue retention (NRR, also called net dollar retention) is the recurring revenue a fixed group of existing customers generates at the end of a period, expressed as a percentage of what the same group generated at the start, including expansion and after churn and contraction. New customers are excluded entirely. Above 100% means the existing base grew on its own; it does not mean customers are staying, because heavy expansion from a few accounts can cover substantial churn among the rest.
Learn moreMonthly Recurring Revenue (MRR)
Monthly recurring revenue (MRR) is the monthly-normalised value of every active paid subscription at a point in time: monthly plans at face value, quarterly plans divided by three, annual plans divided by twelve, plus recurring add-ons and less active discounts. It is a snapshot of contracted run rate rather than an accounting figure, so it deliberately excludes one-off charges, setup fees, usage overages and refunds, and it has no definition in GAAP or IFRS.
Learn moreSaaS Quick Ratio
The SaaS quick ratio divides new plus expansion MRR by churned plus contraction MRR, showing how much recurring revenue a company adds for every unit it loses; above 1 the business is growing net of losses. It shares a name with the accounting quick ratio — a balance-sheet liquidity measure of current assets to current liabilities — but the two are unrelated, use different inputs and answer different questions.
Learn moreAverage Revenue Per User (ARPU)
Average revenue per user (ARPU) is monthly recurring revenue divided by the number of active paying customers, giving the blended monthly value of a single account. It is frequently written ARPA — average revenue per account — and the distinction matters for any product where one account contains several seats, because dividing by seats and dividing by accounts produce different numbers and answer different questions.
Learn moreExpansion MRR: frequently asked questions
What counts as expansion MRR?
Is expansion MRR the same as upsell?
Do reactivations count as expansion MRR?
Why does expansion MRR matter more than new MRR?
How do I increase expansion revenue?
Stop recalculating Expansion MRR by hand.
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