What This Template Is For
A billing migration is one of the highest-risk operations a product team can execute. Every active subscriber, stored payment method, trial period, coupon, and invoice history needs to move from one system to another without a single missed charge or double-billing event. The blast radius of a mistake is immediate: failed renewals, customer support tickets, and lost revenue.
This template provides a structured plan for migrating billing systems. It covers provider evaluation, data mapping, migration sequencing, rollback criteria, and post-migration verification. It applies whether you are switching from Stripe to a different processor, moving from a homegrown billing system to a third-party provider, or restructuring pricing tiers entirely.
Use this alongside the PRD Template if the billing migration is part of a larger product initiative. If the migration involves API contract changes for downstream consumers, pair it with the Feature Specification Template. For guidance on how pricing model changes feed into broader product direction, see the Product Strategy Handbook.
Score the business case for migration with the RICE Calculator before committing engineering resources.
How to Use This Template
- Begin by documenting your current billing state. Map every plan, add-on, coupon, and trial configuration in your existing system before evaluating alternatives.
- Define migration scope. Are you moving all customers at once (big-bang) or migrating cohorts over time (rolling)? The choice depends on your subscriber count, contract types, and engineering capacity.
- Build the data mapping table. Every field in the old system needs a corresponding destination in the new system. Flag fields that have no direct equivalent.
- Write rollback criteria before migration day, not after. Define the specific thresholds (failed charge rate, support ticket volume) that trigger a rollback.
- Plan the communication sequence. Customers need advance notice if their billing date, invoice format, or payment method storage changes.
- Run a shadow period where both systems process charges in parallel (one live, one simulated) to validate parity.
The Template
Migration Overview
| Field | Details |
|---|---|
| Project Name | [Name] |
| Current Provider | [Provider name and plan] |
| Target Provider | [Provider name and plan] |
| Migration Owner | [PM or Engineering Lead] |
| Engineering Lead | [Name] |
| Finance Stakeholder | [Name] |
| Target Start Date | [Date] |
| Target Completion | [Date] |
| Migration Strategy | Big-Bang / Rolling Cohort / Parallel Run |
Business Justification. [2-3 sentences: why is this migration happening? Cost reduction, missing features, compliance, scalability?]
Success Criteria.
- ☐ Zero double-billing events
- ☐ Failed charge rate stays below [X]% during migration window
- ☐ All active subscriptions transferred with correct billing dates
- ☐ Revenue reconciliation within $[X] tolerance for first billing cycle
- ☐ Customer support ticket volume stays below [X]% increase
Current State Inventory
Plans and Pricing.
| Plan Name | Monthly Price | Annual Price | Active Subscribers | Trial Period | Billing Cycle |
|---|---|---|---|---|---|
| [Plan 1] | $[X] | $[X] | [Count] | [Days] | [Monthly/Annual] |
| [Plan 2] | $[X] | $[X] | [Count] | [Days] | [Monthly/Annual] |
Add-Ons.
| Add-On Name | Price | Billing Model | Active Count |
|---|---|---|---|
| [Add-on 1] | $[X]/mo | Per-seat / Flat / Usage | [Count] |
Active Coupons and Discounts.
| Coupon Code | Discount | Expiration | Active Redemptions |
|---|---|---|---|
| [Code] | [% or $] | [Date] | [Count] |
Stored Payment Methods.
| Method Type | Count | Notes |
|---|---|---|
| Credit/Debit Card | [Count] | [Tokenized via X] |
| ACH/Bank Transfer | [Count] | |
| PayPal | [Count] | |
| Invoice/PO | [Count] | [Net terms] |
Data Mapping
| Source Field (Old System) | Target Field (New System) | Transform Required | Notes |
|---|---|---|---|
customer_id | customer.id | UUID mapping | [Details] |
plan_id | price.id | Manual mapping | [Old plan X = new price Y] |
card_token | payment_method.id | Re-tokenization | [Details] |
next_billing_date | subscription.current_period_end | Date format | [Details] |
coupon_code | promotion_code | Code recreation | [Details] |
trial_end | subscription.trial_end | Timestamp | [Details] |
Fields with no direct equivalent:
| Source Field | Resolution |
|---|---|
| [Field] | [Drop / Custom field / Manual process] |
Migration Sequence
Phase 1: Infrastructure Setup (Week 1-2)
- ☐ Provision target provider account and API keys
- ☐ Configure webhook endpoints in target system
- ☐ Set up staging environment with test data
- ☐ Build data migration scripts
- ☐ Create monitoring dashboards for charge success rates
Phase 2: Shadow Period (Week 3-4)
- ☐ Run parallel charge simulation (target system processes in test mode)
- ☐ Compare charge amounts, timing, and customer IDs between systems
- ☐ Validate webhook event parity
- ☐ Test refund, upgrade, and downgrade flows in target system
- ☐ Load-test target system with peak transaction volume
Phase 3: Cohort Migration (Week 5-8)
| Cohort | Description | Size | Migration Date | Rollback Deadline |
|---|---|---|---|---|
| 1 | Internal/test accounts | [N] | [Date] | [Date] |
| 2 | Free tier / trial users | [N] | [Date] | [Date] |
| 3 | Monthly subscribers (low MRR) | [N] | [Date] | [Date] |
| 4 | Annual subscribers | [N] | [Date] | [Date] |
| 5 | Enterprise / custom contracts | [N] | [Date] | [Date] |
Phase 4: Decommission (Week 9-10)
- ☐ Disable charge creation in old system
- ☐ Redirect all webhooks to target system
- ☐ Archive old system data per retention policy
- ☐ Update internal documentation and runbooks
- ☐ Close old provider account
Rollback Plan
| Trigger | Threshold | Action |
|---|---|---|
| Failed charge rate | > [X]% of cohort within 24 hours | Pause migration, revert cohort to old system |
| Double-billing detected | Any confirmed instance | Immediate pause, refund affected customers, investigate |
| Webhook delivery failure | > [X]% failures over 1 hour | Switch webhook routing back to old system |
| Support ticket spike | > [X]x normal volume within 4 hours | Pause next cohort, investigate root cause |
Rollback procedure:
- [Step-by-step instructions for reverting a cohort to the old system]
- [How to communicate the rollback to affected customers]
- [How to reconcile charges that occurred during the partial migration]
Customer Communication Plan
| Timing | Audience | Channel | Message |
|---|---|---|---|
| T-30 days | All customers | Migration announcement, what to expect | |
| T-7 days | Current cohort | Specific migration date, action required (if any) | |
| T-0 | Current cohort | In-app banner | Migration happening today |
| T+1 | Migrated cohort | Confirmation, new invoice portal link | |
| T+7 | Migrated cohort | Follow-up, support contact for issues |
Revenue Reconciliation
| Metric | Pre-Migration Baseline | Post-Migration Target | Tolerance |
|---|---|---|---|
| MRR | $[X] | $[X] | +/- $[X] |
| Failed charge rate | [X]% | [X]% | +[X]% max |
| Involuntary churn rate | [X]% | [X]% | +[X]% max |
| Average days to payment recovery | [X] | [X] | +[X] days max |
Open Questions
| # | Question | Owner | Status | Decision |
|---|---|---|---|---|
| 1 | [Question] | [Name] | Open | |
| 2 | [Question] | [Name] | Open |
Filled Example: Stripe to Paddle Migration
Migration Overview
| Field | Details |
|---|---|
| Project Name | Billing Provider Migration: Stripe to Paddle |
| Current Provider | Stripe (Billing + Payments) |
| Target Provider | Paddle (Merchant of Record) |
| Migration Owner | Sarah Chen, Senior PM |
| Engineering Lead | Marcus Johnson |
| Finance Stakeholder | Lisa Park, VP Finance |
| Target Start Date | April 1, 2026 |
| Target Completion | June 15, 2026 |
| Migration Strategy | Rolling Cohort |
Business Justification. Moving to Paddle as merchant of record eliminates sales tax collection and remittance overhead across 40+ jurisdictions. This saves approximately 15 hours/month of finance team time and $24K/year in tax compliance software costs. Paddle also handles VAT for EU customers, removing our largest compliance risk.
Success Criteria.
- ☑ Zero double-billing events
- ☑ Failed charge rate stays below 2% during migration window
- ☑ All 4,200 active subscriptions transferred with correct billing dates
- ☑ Revenue reconciliation within $500 tolerance for first billing cycle
- ☑ Customer support ticket volume stays below 20% increase
Cohort Plan
| Cohort | Description | Size | Migration Date | Status |
|---|---|---|---|---|
| 1 | Internal team accounts | 12 | April 1 | Complete |
| 2 | Free tier users | 890 | April 8 | Complete |
| 3 | Monthly Starter plan | 1,850 | April 22 | Complete |
| 4 | Monthly Pro plan | 620 | May 6 | Complete |
| 5 | Annual subscribers | 540 | May 20 | Complete |
| 6 | Enterprise contracts | 38 | June 1 | Complete |
Key Takeaways
- Inventory every plan, coupon, trial, and stored payment method before starting
- Use rolling cohort migration to limit blast radius on large subscriber bases
- Define rollback triggers and thresholds before migration day, not during
- Run a shadow period with parallel charge simulation to validate data mapping
- Communicate proactively to customers at T-30, T-7, T-0, and T+1 days
About This Template
Created by: Tim Adair
Last Updated: 3/5/2026
Version: 1.0.0
License: Free for personal and commercial use