How to Grandfather Old Customers at Old Prices

Set up grandfathering policies that retain customers while protecting margins during price increases.

1. Calculate the financial impact of grandfathering. Run the numbers on lost revenue versus customer acquisition costs. If your CAC is $500 and you're raising prices 20%, grandfathering makes sense if the customer's annual value exceeds $2,500. Factor in lifetime value, not just annual revenue.
2. Set a hard expiration date. Legacy pricing should sunset after 12-24 months maximum. Communicate this upfront: 'Current customers keep existing rates through December 31, 2025.' This gives customers time to adjust while protecting your margins long-term.
3. Segment customers by value tier. Don't grandfather everyone equally. Your top 20% of customers might get permanent legacy rates, the middle 60% get 12-month grandfathering, and the bottom 20% move to new pricing immediately. Use actual revenue numbers to draw these lines.
4. Build stepped increases for high-value accounts. For customers you want to keep but can't afford to grandfather indefinitely, implement 6-month stepped increases. Move them from old pricing to new pricing in 25% increments every six months until they reach market rates.
5. Document the policy in writing. Send written notice explaining who gets grandfathered, for how long, and what happens next. Include this in new contracts going forward. Clear documentation prevents disputes and sets expectations for future price changes.
6. Track grandfathered revenue separately. Create separate revenue buckets in your books for legacy versus current pricing. Monitor what percentage of total revenue comes from grandfathered accounts monthly. If it exceeds 30%, accelerate the sunset timeline.