Starting Monthly Recurring Revenue

What it measures

Starting MRR is the opening balance for your period — the previous month's Closing MRR carried forward, unchanged. It is the fixed baseline against which you measure new, expansion, contraction, and churned revenue during the current period. It is not recomputed from active contracts; it is a direct reference to where last month ended.

Why it matters

You need a clean opening position because MRR movement only makes sense in context. Finance reads Starting MRR to anchor the bridge from prior month to current month — it is the leftmost bar of the revenue waterfall. Operations uses it to set quotas and churn budgets against a known base. Investors look at whether the denominator for your growth-rate calculation is stable or volatile, since a noisy opening balance makes every downstream growth number untrustworthy.

How to read it

Starting MRR should be identical to the previous month's Closing MRR — no restatement, no catch-up. If the two numbers disagree, you have a data integrity issue, not a business event. Compare Starting MRR month-to-month to see if your base is growing (good) or shrinking (last month's net-new was negative). Always pair it with month-end Closing MRR to read the *motion*: started $100K, ended $111K means +11% month-on-month. On its own, Starting MRR tells you almost nothing — its value is as the anchor for everything that moves on top of it.

What good looks like

Watch-outs

• Not locking it to the prior period's Closing MRR. Starting MRR must equal last month's ending balance exactly; any gap means the waterfall no longer reconciles and growth math is built on sand.
• Restating or adjusting it after the period has begun. Once the prior period closes, Starting MRR is frozen — corrections belong in the prior period's Closing MRR and only then flow forward.
• Confusing it with Closing MRR or the month's net-new. It is neither an ending balance nor a measure of motion — it is purely a carry-forward of where you started.
• Letting timing leakage contaminate it. A customer who signs on day one of the new month is New MRR, not Starting MRR; one who churns on the last day of the prior month is already excluded — misclassifying either inflates or deflates the opening base.

Worked example