A phone loses value because buyers pay for its remaining usefulness and certainty, not because a fixed percentage disappears each month. The pattern varies by model, condition and market timing.
The main drivers
| Driver | Why it changes value |
|---|---|
| New-generation launch | Creates a newer reference point and adds outgoing stock |
| Remaining support | A shorter secure life reduces usefulness |
| Battery and condition | Creates immediate repair or replacement costs |
| Storage and variant | Changes the pool of suitable buyers |
| Repair history | Can increase uncertainty or prove responsible maintenance |
| Supply and demand | Popular models with constrained used supply can remain stronger |
Depreciation is not the same as ownership cost
A £1,000 phone sold for £500 has lost £500 in device value. It may still cost more than that to own once airtime, accessories, insurance and repairs are included.
Measure with sold evidence
Compare genuinely completed sales or firm trade-in quotes for the exact storage, condition and region. Asking prices show seller ambition; they do not show value achieved.
Use ranges
For a future estimate, record a conservative, central and optimistic outcome. Use the conservative figure in affordability decisions and update it near the planned sale date.
Launch price can mislead
When a model is heavily discounted soon after launch, measuring depreciation from the original recommended price exaggerates the loss experienced by a later buyer. Use the amount actually paid and compare it with the amount actually recoverable.
Repair decisions affect residual value
A documented battery replacement may support a sale; a poor screen repair or unresolved parts warning may reduce trust. Compare the repair cost with both the extra useful life and the likely change in net sale value. Do not assume every pound spent on repair returns a pound at sale.
Related guides
- Phones That Hold Their Value Best
- Phones That Lose Value Fastest
- Calculate Resale Value
Sources and date checked
Official information checked 26 July 2026. Product prices, contract terms and retailer policies can change, so verify the current document before acting.
