What Is an ARR Bridge? (And How to Build One)
What is an ARR Bridge?
An ARR bridge (also called an ARR waterfall or ARR walk) is a visualization that shows how your Annual Recurring Revenue changed from one period to the next. It breaks the change into five components: Beginning ARR, New Business, Expansion, Contraction, and Churn — arriving at your Ending ARR.
Think of it like a bank statement for your recurring revenue. Instead of just showing the balance, it shows every deposit and withdrawal that got you there.
Quick definition: An ARR bridge answers the question "why did our ARR change?" by decomposing the movement into its five sources. It is the standard format used in SaaS board decks and investor updates worldwide.
Formula: Ending ARR = Beginning ARR + New Business + Expansion − Contraction − Churn
Why the ARR Bridge Matters
A single ARR number tells you almost nothing. A company growing 30% that's masking 15% churn with aggressive new logo acquisition looks very different from one growing 30% with 5% churn and healthy expansion. The ARR bridge reveals which story is yours.
This is why every serious board deck includes an ARR bridge. Investors and board members want to see the components, not just the total. It answers questions like:
- Is growth coming from new customers or existing customer expansion?
- How much revenue are we losing to churn and contraction?
- Is our net retention healthy enough to sustain growth as new logo acquisition slows?
The Five Components
Beginning ARR — Your starting point. The total ARR at the start of the period.
New Business — ARR from customers who were not customers in the prior period. This is your new logo revenue.
Expansion — Increased ARR from existing customers. This includes upsells, cross-sells, seat additions, and pricing increases. Expansion is what drives Net Dollar Retention above 100%.
Contraction — Decreased ARR from existing customers who are still customers but spending less. Downgrades, seat reductions, or discount applications.
Churn — ARR from customers who left entirely. This is the revenue you lost from cancelled or non-renewed contracts. To measure it consistently, see our guide on calculating churn rate.
Ending ARR = Beginning ARR + New + Expansion − Contraction − Churn
Together, these components feed into your Gross Revenue Retention and Net Dollar Retention metrics — the two most important measures of retention health.
Common Mistakes
Mixing up contraction and churn. A customer who downgrades from $50K to $30K is contraction ($20K), not churn. A customer who cancels entirely is churn ($50K). Getting this wrong inflates your churn numbers and makes your business look worse than it is.
Not accounting for timing. If a customer signs mid-month, how do you count them? Most companies use the start of the next full month, but consistency matters more than the specific rule. Pick a methodology and stick with it.
Double-counting expansion and new business. If an existing customer buys a second product, that's expansion — not new business. New business should only include revenue from net-new logos.
How to Build Your ARR Bridge
The manual approach involves exporting your customer data into a spreadsheet, comparing each customer's ARR between periods, and categorizing every change. This works at 20 customers but becomes unsustainable at 100+.
The automated approach uses a tool that ingests your customer data and handles the categorization automatically. Upload a CSV with customer names, ARR amounts, and dates, and get an instant ARR bridge with all five components broken out.
ARRGuide does exactly this — upload your data and get a complete ARR bridge, retention metrics, and customer-level detail in under 60 seconds. Start your free trial →