Legacy Software Modernisation Cost UK: Rebuild, Replatform or Replace?
The server is end-of-life, the developer who understood the system has retired, and the quote range spans £20,000 to £400,000. This guide puts real UK numbers on the three ways out: rebuild from scratch, replatform onto modern hosting, or replace with an off-the-shelf product. It covers the price bands per route, the day rates behind them, a 40-person worked example priced three ways (£40,680 vs £70,400 vs £136,455 over three years), the five hidden costs estimates miss, and a decision framework for choosing — plus six ways to cut the bill.
