What is a good expansion rate?

Above 5% monthly expansion rate is strong for growth-stage SaaS. Top-performing companies with usage-based or seat-based pricing achieve 8-15% monthly expansion rates.

How does expansion MRR affect NRR?

Expansion MRR is the key driver of net revenue retention (NRR) above 100%. If expansion revenue exceeds churned and contracted revenue, NRR exceeds 100%, meaning existing customers grow in value over time.

How do you track expansion MRR in Stripe?

Compare subscription amounts before and after changes for existing customers. Stripe subscription update events (customer.subscription.updated) show plan and quantity changes that represent expansion.

What Is Expansion MRR? Sources, Formula & Impact on NRR

Q: What is expansion MRR?

Expansion MRR is the additional monthly recurring revenue generated from existing customers through upgrades, add-ons, seat increases, and cross-sells. It does not include revenue from new customers.

Definition

Expansion MRR is the increase in monthly recurring revenue from existing customers compared to the prior period. It captures only revenue growth from the current customer base — revenue from new customers is classified as New MRR.

Sources of Expansion MRR

Expansion MRR comes from five primary sources:

Plan upgrades: A customer moves from a $50/month plan to a $150/month plan, adding $100 in expansion MRR.
Seat increases: A team grows from 10 to 25 seats at $10/seat, adding $150 in expansion MRR.
Add-ons: A customer purchases an additional module or feature for $30/month.
Usage overages: A customer exceeds their plan limits and pays for additional usage.
Cross-sells: A customer subscribes to a second product from the same company.

Expansion MRR Formula

Expansion MRR = Sum of MRR increases from existing customers in a period

Example: In April, three existing customers upgraded. Customer A added $200/month, Customer B added $50/month, and Customer C added $100/month. Total Expansion MRR = $200 + $50 + $100 = $350.

Expansion Rate

Expansion rate measures expansion MRR as a percentage of starting MRR:

Expansion Rate = (Expansion MRR ÷ Starting MRR) × 100

Example: If your starting MRR is $100,000 and you generated $6,000 in expansion MRR, your expansion rate is $6,000 ÷ $100,000 × 100 = 6%.

Expansion Rate (Monthly)	Interpretation
> 5%	Strong. Common in usage-based or seat-based pricing models.
2-5%	Healthy. Typical for mid-market SaaS with tiered pricing.
< 2%	Low. May indicate limited upsell paths or flat pricing structure.

Impact on Net Revenue Retention

Expansion MRR is the only way to achieve net revenue retention (NRR) above 100%. NRR above 100% means your existing customers are worth more this period than last period, even after accounting for churn and contraction.

NRR = (Starting MRR + Expansion MRR - Churned MRR - Contraction MRR) ÷ Starting MRR × 100

The best SaaS companies achieve 120-140% annual NRR. This is only possible when expansion revenue significantly exceeds losses from churn and contraction. Companies with NRR above 130% can grow revenue even with zero new customer acquisition.

How to Drive Expansion Revenue

Expansion does not happen by accident. These strategies systematically increase expansion MRR:

Usage limits with clear upgrade paths: Set plan limits that growing customers will naturally hit. Make upgrading frictionless with one-click plan changes.
Tiered feature gating: Reserve high-value features (analytics, API access, SSO, audit logs) for higher tiers to create upgrade motivation.
Proactive outreach: Identify customers approaching plan limits and reach out before they hit friction. A well-timed upgrade suggestion converts 2-3x better than a forced limit.
In-app triggers: Show upgrade prompts when customers attempt to use features outside their current plan. Contextual prompts convert 4-5x better than email campaigns.
Seat-based pricing: Revenue naturally expands as customer teams grow. This is the most common expansion mechanism for B2B SaaS.

Tracking Expansion in Stripe

Stripe records subscription changes that produce expansion MRR. To track expansion:

Monitor customer.subscription.updated events: Compare the previous_attributes to the current subscription to detect plan or quantity increases.
Compare invoice amounts: For each existing customer, compare the current period invoice total to the prior period. Any increase represents expansion.
Filter by customer age: Only count MRR increases from customers whose first subscription started before the current period. This separates expansion from new MRR.