Buy the tool. Or build your own?
Compare subscription software with a custom build over one to five years. Put implementation, licences, maintenance and hosting into the same GBP view.
The cost over time.
Year-end cumulative costs. One-off costs are included once, in year one.
| Year | Buy | Build |
|---|---|---|
| 1 | £20,500 | £42,600 |
| 2 | £38,500 | £52,200 |
| 3 | £56,500 | £61,800 |
How the numbers work.
- Buy annual recurring = (users × monthly licence + monthly platform fee) × 12 + other annual costs. Add one-off buy setup once.
- Build annual recurring = maintenance + hosting/licences + other annual costs. Add initial development, migration and training once.
- The table accumulates each route at the end of each year. “Build at or below buy” is the first year-end that meets that condition, only within the selected horizon. It is not an exact monthly crossover.
All money values are GBP. Keep VAT treatment consistent across inputs. Outputs are indicative, not a quote or a guarantee. Model reviewed October 2026.
Explore custom business softwareBefore you decide.
Does the cheaper option mean it is the right choice?
No. Compare workflow fit, delivery time, data ownership, security, integration constraints and supplier risk alongside the cost. A hybrid approach may be appropriate.
Are VAT and future price increases included?
No. Use all inputs on a consistent basis, normally excluding VAT where recoverable. The model does not forecast inflation, tax treatment, licence increases or user growth.
How do I estimate the custom build?
Start with the project cost calculator, then get a scoped proposal. Include maintenance and internal ownership rather than comparing a build quote against licences alone.