MRR, ARR, churn: the 10 SaaS KPIs to monitor weekly in 2026

Direct answer. A SaaS founder must read 10 indicators every week to stay in steering mode rather than reactive mode: MRR, ARR, new MRR, expansion MRR, churn MRR, net MRR, NRR, GRR, ARPA and magic number / burn multiple. This article provides definitions, formulas, market benchmarks and the French accounting conventions needed to build a dashboard that holds up from board reporting to due diligence.

Monthly reviews exist for boards and investors. They are not enough to steer a business. Over 28 days, a SaaS can drift from healthy growth to excessive burn without any monthly signal flagging it.

A weekly cadence sets the right rhythm:

• it triggers arbitrations before month-end;
• it isolates one-off commercial shocks from structural deterioration;
• it aligns Sales, Marketing, CSM and Finance on the same definitions.

See our reference dashboard article for SMEs and the 5 essential SME KPIs for 2026 for cross-sector basics.

3.1. MRR — Monthly Recurring Revenue#

Definition. Contractualised recurring revenue, normalised over a month.

$$ \text{MRR} = \sum_{i=1}^{n} \frac{\text{Annual contract value}_i}{12} $$

Include: recurring subscriptions (monthly or annual normalised). Exclude: one-off services, set-up fees, migration fees, contractually uncommitted usage.

3.2. ARR — Annual Recurring Revenue#

Definition. ARR = MRR × 12. Standard external metric for investors and acquirers (see our enterprise valuation service).

3.3. New MRR#

MRR generated by new customers signed during the week. Strictly distinct from expansion.

3.4. Expansion MRR#

Additional MRR on existing customers: upsell, cross-sell, additional seats, plan upgrades, options.

3.5. Churn MRR#

MRR lost during the week from cancellations or downgrades.

Distinguish:

• Logo churn: customers lost / customers at start of period.
• Revenue churn: MRR lost / MRR at start of period.

Revenue churn is the only one to use for LTV and payback computations (see our SaaS unit economics guide).

3.6. Net MRR#

$$ \text{Net MRR} = \text{New MRR} + \text{Expansion MRR} - \text{Churn MRR} $$

3.7. NRR — Net Revenue Retention#

$$ \text{NRR} = \frac{\text{Cohort end MRR} - \text{Churn MRR} + \text{Expansion MRR}}{\text{Cohort start MRR}} $$

3.8. GRR — Gross Revenue Retention#

$$ \text{GRR} = \frac{\text{Cohort end MRR} - \text{Churn MRR}}{\text{Cohort start MRR}} $$

GRR excludes expansion and reflects pure cancellation risk. ≥ 90% is expected for B2B mid-market SaaS.

3.9. ARPA — Average Revenue Per Account#

$$ \text{ARPA} = \frac{\text{Total MRR}}{\text{Active accounts}} $$

Tracking ARPA flags drift toward downmarket (ICP slipping toward SMB) or upmarket (enterprise concentration).

3.10. Magic number and burn multiple#

Magic number (sales efficiency):

$$ \text{Magic number} = \frac{\Delta \text{ARR (quarter)} \times 4}{\text{S&M (previous quarter)}} $$

Burn multiple (overall capital efficiency):

$$ \text{Burn multiple} = \frac{\text{Net burn (quarter)}}{\Delta \text{ARR (quarter)}} $$

SaaS KPIs are not accounting figures. But they must reconcile with the general ledger.

Three bridges to formalise:

1. MRR vs recognised revenue. Annual subscriptions invoiced upfront are booked as deferred revenue (PCG art. 944-94). Monthly recognised revenue should be close to MRR — a structural gap signals a definition issue.
2. Churn vs credit notes. Credit notes (account 709) must be deducted from MRR of the period concerned, not the period of issue.
3. Expansion vs invoiced upsells. Every expansion event must be traceable to an invoice (account 706 – Service revenue).

The chartered accountant's role is to guarantee this reconciliation at each close. That is what makes these KPIs opposable to an investor or acquirer (see our outsourced CFO service).

See our reviews of Pennylane, Qonto and Power BI. Stack choice is not neutral: consistency between billing source and accounting drives KPI reliability.

Four recurring red flags:

1. MRR definition not frozen: each team uses a variant. MRR must be defined in writing (what is in, what is out, how multi-year commitments are treated) and frozen for at least 12 months.
2. Expansion poorly isolated: blending expansion into new MRR artificially inflates Sales productivity and hides CSM productivity.
3. Churn computed on ARR rather than monthly MRR: for a portfolio heavy in annual contracts, churn appears null for 11 months then spikes at month 12. Smooth by cohort.
4. No bridge to the P&L: serious investors systematically request the bridge between last-month MRR and recognised revenue. Its absence is a negative signal.

ARR has become a buzzword. Many founders present an ARR without specifying:

• whether it includes uninvoiced expansion;
• whether it includes trial or POC customers;
• whether it includes cancelled-but-still-billing customers.

In due diligence or in a pre-seed round, an "optimistic" ARR is systematically reconciled to billing. The gap weighs on valuation. A conservative, opposable ARR is always preferable to an optimistic ARR that will be revised down.

• The definition of each of the 10 KPIs, in writing.
• The cadence: weekly for steering, monthly for the board.
• The single source: who owns the figure, in which tool, with which accounting validation.
• Alert thresholds: at what churn or NRR level the board is escalated.
• The review schedule: a fixed weekly slot, non-negotiable.

• E-invoicing (2026–2027 roll-out): forces stricter traceability between MRR and invoices. See our piece on payment delegation and cash protection.
• VAT on digital services: for B2C, place of taxation = place of consumption. MRR collected is not always MRR taxable in France.
• NRR under pressure: 2024–2025 external benchmarks show falling SMB NRR. Track cohort by cohort.

• Written definition of the 10 KPIs, validated by management and finance
• MRR reconciled monthly to recognised revenue
• Churn and expansion isolated in MRR, not ARR
• NRR and GRR tracked by cohort
• ARPA monitored for ICP drift
• Magic number and burn multiple reviewed quarterly
• Weekly dashboard, fixed time slot
• Single source between billing, accounting and BI
• Written alert-threshold convention
• MRR / revenue bridge always available