ARR vs MRR — A Field Guide

ARR and MRR measure the same underlying thing — committed recurring revenue — at two different time scales, and mixing them up in a board deck or a pricing model is one of the most common SaaS finance mistakes. MRR is the monthly lens: useful for tracking short-term momentum, churn, and expansion. ARR is the annual lens: useful for valuation multiples, fundraising conversations, and comparing yourself to other companies who quote in annual terms. Neither is "more correct" — they answer different questions.

The definitions and the simple conversion

MRR is the total recurring revenue you can count on collecting each month from active subscriptions, normalised to a monthly figure regardless of billing frequency. ARR is simply MRR × 12. The conversion is trivial in principle but gets misused in practice: a company that signs a large annual contract in January should not report a spike in that month's MRR equal to the full annual value — the correct treatment is to recognise 1/12th of the contract value as MRR each month, the same as if the customer paid monthly.

SELECT
  DATE_TRUNC('month', period_start) AS month,
  SUM(CASE
    WHEN billing_interval = 'annual' THEN amount / 12.0
    WHEN billing_interval = 'monthly' THEN amount
  END) AS mrr
FROM subscriptions
WHERE status = 'active'
GROUP BY 1
ORDER BY 1;

Why MRR is the better operating metric

MRR moves fast enough to be actionable. If churn spikes or a pricing change backfires, MRR shows it within a month; ARR, being a 12x multiple of the same number, shows the same signal but with less granularity for month-over-month decision making. Most SaaS operating dashboards should be built around MRR components — new MRR, expansion MRR, contraction MRR, churned MRR — because that breakdown is where the actual story lives, not in the top-line number alone.

Why ARR is the fundraising and benchmarking metric

Investors, acquirers, and most public SaaS comparables talk in ARR because it is the annualised, more intuitive number for evaluating a business at a point in time — "we're at $2M ARR" reads more naturally than "we're at $167K MRR" even though they describe the same state. Valuation multiples (EV/ARR) are quoted against ARR, and most SaaS benchmarking reports (Bessemer's state-of-the-cloud, OpenView, etc.) use ARR bands to segment companies. Use ARR when you're talking to people outside the day-to-day operation of the business.

Common mistakes that inflate the numbers

The most common distortion is counting non-recurring revenue in either figure — one-time setup fees, professional services, or a one-off annual contract that will not renew should not be in MRR/ARR at all. The second is double-counting expansion: if a customer upgrades mid-month, prorate the change rather than adding the full new-tier amount on top of the old. The third is including trial or freemium accounts with $0 committed revenue as if they contribute to the recurring base — they don't, until they convert.

What good growth looks like

Growth-stage SaaS benchmarks (from sources like the SaaS Capital survey and Bessemer's Cloud 100 data) generally put "good" net MRR growth at 10-20% month-over-month for early-stage companies, tapering as ARR scales past a few million — sustained 15%+ MoM growth past $1M ARR is rare and usually a signal of an unusually strong product-market fit. Net revenue retention (expansion minus churn as a percentage of starting MRR) above 100% is the more telling long-term indicator than gross new MRR, since it shows the existing base is growing on its own.

Wrapping up

Use MRR to run the business month to month and ARR to describe the business to people who think in annual terms. Keep both numbers built from the same underlying subscription ledger with proration handled correctly, exclude non-recurring revenue, and always look at the MRR components — not just the net figure — before deciding whether growth is healthy or one good quarter away from a churn problem.