What monthly recurring revenue actually measures
MRR is a run-rate, not an accounting result. It answers one question: if nothing changed today, how much would your contracted subscriptions be worth for one month? That makes it the cleanest single number for judging the health of a subscription business, and it is why investors ask for it before they ask for your income statement.
Three figures get confused with MRR, and keeping them apart is most of the discipline. Billings is cash you invoiced this month — an annual prepay lands as twelve months of cash at once, which makes billings lumpy and useless as a growth signal. Recognised revenue under ASC 606 is the portion of each contract you have actually delivered, so a $588 annual plan sold on the 15th recognises about $24 in its first month. MRR ignores both cash timing and recognition schedules and simply values the subscription per month of service. The same annual plan contributes $49 to MRR from the day it starts.
Because MRR sits outside GAAP, nobody audits your definition for you. Write it down, decide what you exclude, and stop changing it.
The formula: normalising every billing term to one month
Divide each recurring invoice by the number of months it covers, multiply by the number of accounts on that term, and add the results. A monthly invoice divides by 1, a quarterly invoice by 3, an annual prepay by 12, a two-year prepay by 24. That single divisor is the whole trick, and it is what stops a term mix from distorting the total.
Normalise rather than count cash and your MRR stops jumping every January and sagging every February purely because of when renewals fall. Two companies with identical customers and identical prices then report identical MRR even if one sells annual contracts and the other bills monthly.
The second half of the calculation is the movement, and it is the half that tells you something. Any month's ending MRR equals the starting MRR plus four flows: new MRR from accounts that were not paying last month, expansion from accounts that grew, contraction from accounts that shrank but stayed, and churned MRR from accounts that left. Their sum is net new MRR. Two companies can both add $500 of net new MRR while one adds $600 of new business against $100 of losses and the other adds $5,000 against $4,500 — those are completely different businesses, and only the movement view separates them.
Divide the gains by the losses and you get the SaaS quick ratio, a one-number summary of how leaky the bucket is. A quick ratio of 4 means four dollars of MRR arrive for every dollar that leaks out. Below 1 the book shrinks no matter how good the sales team looks.
Worked example: a 417-account book on three billing terms
Take a small software company with 320 accounts paying $49 a month, 12 accounts paying $1,500 a quarter, and 85 accounts on a $588 annual prepay. During the month it signed $900 of new MRR, expanded $260, lost $95 to downgrades and $520 to cancellations.
- Monthly plans. 320 × $49 = $15,680. No divisor needed — the invoice already covers one month.
- Quarterly plans. $1,500 ÷ 3 = $500 per month each. 12 × $500 = $6,000.
- Annual plans. $588 ÷ 12 = $49 per month each. 85 × $49 = $4,165. Note this is the same $49 as the monthly plan: the annual price here is twelve months at no discount.
- Total MRR. $15,680 + $6,000 + $4,165 = $25,845.
- Implied ARR. $25,845 × 12 = $310,140.
- ARPA. 320 + 12 + 85 = 417 accounts. $25,845 ÷ 417 = $61.98. The twelve quarterly accounts at $500 a month pull the average well above the $49 list price.
- Net new MRR. $900 + $260 − $95 − $520 = $545.
- Starting MRR. $25,845 − $545 = $25,300, so net MRR growth is $545 ÷ $25,300 = 2.15% for the month, roughly 29% annualised.
- Quick ratio. ($900 + $260) ÷ ($95 + $520) = $1,160 ÷ $615 = 1.89.
- Gross MRR churn. $520 ÷ $25,300 = 2.06% a month. Compounded, that would remove about 22% of the opening book over a year if nothing were added back.
The headline looks fine — growth is positive and the book is expanding. The quick ratio is what should worry you: at 1.89 the company burns roughly half of its gross additions replacing revenue it already had.
How to read your MRR, and which of the supporting numbers matter
Read net new MRR before you read total MRR. The total tells you how big you are; net new tells you whether the last month worked. A month with $6,000 of new business and $6,000 of churn is a flat month, and the total MRR figure hides that completely.
Then read the two ratios. Gross MRR churn is the fraction of your opening book that cancelled. As a working rule of thumb, self-serve businesses selling to very small companies live with 3–5% a month, mid-market products aim for around 1%, and enterprise contracts should be well below that because they renew annually rather than monthly. The number only means something against your own trend and your own segment.
The quick ratio compares gains to losses and is the fastest read on efficiency: roughly 4 or better is strong, 2 to 4 is workable, and under 1 means you are shrinking. If your quick ratio is low while net new MRR is still positive, you have a retention problem being masked by sales spend — fix the leak before you buy more traffic.
Finally, treat implied ARR as arithmetic, not a forecast. MRR × 12 assumes today's book runs unchanged for a year, which it will not: some of it will churn and some will expand. If you want a real twelve-month number, project the movement forward with the subscription revenue forecast calculator, or build ARR from signed contract terms with the ARR calculator.
Normalisation multipliers by billing term
| Billing term | Invoices per year | Divide invoice by | Annualise MRR by | $1,200 invoice → MRR |
|---|---|---|---|---|
| Monthly | 12 | 1 | × 12 | $1,200.00 |
| Quarterly | 4 | 3 | × 12 | $400.00 |
| Semi-annual | 2 | 6 | × 12 | $200.00 |
| Annual | 1 | 12 | × 12 | $100.00 |
| 2-year prepaid | 0.5 | 24 | × 12 | $50.00 |
| 3-year prepaid | 0.33 | 36 | × 12 | $33.33 |
Multi-year prepays are the case people get wrong most often: a $36,000 three-year deal is $1,000 of MRR, not $12,000 of ARR three times over.
MRR is not revenue, and calling it revenue causes real problems
MRR is a non-GAAP operating metric: it has no standing under GAAP or IFRS. Recognised revenue follows ASC 606: you recognise as you deliver, so a mid-month annual contract produces a fraction of a month of revenue and a large deferred revenue balance. Your MRR and your income statement will never tie exactly, and they are not supposed to.
So never present MRR × 12 as a revenue forecast in anything an investor or auditor will read — label it a run-rate. And if you disclose MRR publicly, expect to defend a stable definition: a company that quietly starts counting usage overages or professional services in MRR is creating a restatement it will have to explain later.
What to leave out of MRR, and the mistakes that inflate it
- One-time fees. Setup, onboarding, implementation, data migration and training are not recurring. They belong in total revenue, never in MRR.
- Variable usage and overages. If the amount changes every month with consumption, it is not committed recurring revenue. Exclude it, or report it as a separate line — never bury it inside MRR.
- Trials and free plans. A 30-day trial with a credit card on file is $0 of MRR until it converts. Counting trials is the fastest way to build a forecast that misses.
- Discounts you actually grant. MRR is net of discounts. A $100 plan sold at 20% off is $80 of MRR for as long as the discount runs, and reverts to $100 only when the customer really starts paying it.
- Taxes and payment fees. Sales tax and VAT are not yours. Card processing fees are a cost, not a reduction in contracted price — net them out of margin, not out of MRR.
- Double-counting annual prepays. Recording the $588 of cash and the $49 of MRR in the same growth chart is the classic error. Pick one basis per chart.
Where MRR sits among the other subscription metrics
MRR is the base that most other subscription metrics are built from, so it is worth knowing which tool answers which question. ARR is the same idea on an annual footing and is the convention for businesses that sell annual or multi-year contracts; if you sell month-to-month, MRR is the more honest unit. ARPA or ARPU is MRR divided by accounts or users and tells you whether growth came from more customers or from bigger ones.
On the retention side, customer churn counts logos while gross MRR churn counts dollars, and the two diverge sharply when your small accounts leave and your large ones stay. Net revenue retention folds expansion back in and is the single number growth-stage investors look at hardest; anything above 100% means your existing customers grow faster than they leave.
For unit economics, MRR feeds customer lifetime value and the LTV to CAC ratio. At company level, MRR growth is one half of the Rule of 40 score, and net burn against net new MRR sets your cash runway. Measure MRR badly and every one of those numbers inherits the error.
Key terms
- MRR
- Monthly recurring revenue — the normalised one-month value of all active subscriptions, excluding one-time and variable charges.
- Net new MRR
- New plus expansion MRR minus contraction and churned MRR. The change in the book during a month.
- ARPA
- Average revenue per account: MRR divided by the number of paying accounts. ARPU is the same idea per user or per seat.
- Expansion vs contraction
- Expansion is extra MRR from an account that stays; contraction is lost MRR from an account that stays. A cancellation is churn, not contraction.
- SaaS quick ratio
- (New + expansion) ÷ (contraction + churned). A measure of how much of your gross growth is consumed replacing lost revenue.
- Run-rate
- Any figure produced by annualising a single period, such as MRR × 12. It describes today, not next year.