ARR Formula: Exact SaaS Calculation Rules

For a set of active recurring contract lines L, annual recurring revenue at time t is:

For each recurring line i:

Equivalently, if the recurring contract value is already normalized over its committed term:

The canonical relationship to MRR is exact:

• L(t): the set of recurring contract or subscription lines active at time t.
• RecurringContractValue(i): the total committed recurring value of line i over its actual recurring term.
• TermInMonths(i): the exact number of months covered by the recurring commitment of line i.
• MonthlyRecurringValue(i): the monthly-normalized recurring value of line i.
• AnnualRecurringValue(i): the annualized recurring value of line i.

A line belongs in ARR if and only if it belongs in MRR. Therefore, include line i only if:

• The charge is recurring by contract.
• The line is active at time t.
• The price belongs to ongoing service rather than a one-time event.
• The recurring term can be normalized consistently.

In set notation:

Exclude from ARR exactly what must be excluded from MRR:

• One-time setup and onboarding fees.
• Professional services and implementation projects.
• Taxes, pass-through charges, and hardware.
• Purely variable non-committed usage.
• Non-recurring credits and one-off adjustments.
• Future contract lines that are not yet active.

ARR is not cash, bookings, billings, or total contract value. It is annualized recurring revenue only.

ARR is not an independent calculation standard. It is derived from the same recurring base as MRR.

Therefore, the following equality must hold without exception under a consistent policy:

If a company reports ARR that cannot be reconciled to twelve times its MRR base, then one of the two numbers is being calculated under a different inclusion or normalization policy.

• Annual contract billed upfront: ARR does not equal collected cash; it equals annualized recurring value, which may numerically match the annual contract value but not for cash-timing reasons.
• Multi-year contract: ARR is not total contract value divided by total years unless the full contract value is entirely recurring and evenly annualizable. One-time fees must still be excluded.
• Mid-year expansion: ARR changes from the effective date of the recurring amendment, not from cash receipt timing.
• Discounts: use the actual recurring committed value after recurring discounts, not the undiscounted list amount.
• Usage commitments: include only the committed recurring base, not purely variable overage revenue without recurring commitment.

Suppose a workspace has the same active recurring base described in the MRR formula page:

• Annual subscription: USD 12,000 for 12 months
• Monthly add-on: USD 300 per month
• Quarterly seat package: USD 900 per 3 months

Then:

Equivalently by line:

A one-time implementation fee of USD 2,500 still contributes 0 to ARR.

ARR is the exact annualized value of the active recurring revenue base and must be fully consistent with MRR.

If a line does not belong in MRR, it does not belong in ARR. If ARR cannot be reconciled to 12 × MRR, the calculation policy is not strict enough.

Core metric pages:

• MRR
• MRR vs ARR
• ARR
• Net New MRR