When a battery replacement beats a new phone

Keeping a working phone and replacing its battery is often the cheapest way to feel new again. Here is how TechWorth decides that without inventing a cost.

TechWorth editorial · Last reviewed 6 September 2026

A tired battery is the most common reason a still-supported phone feels finished. Apple publishes a design cycle life and a retention figure on its batteries page; we store those as sourced constants rather than typing them into this article.

The engine compares a sourced battery service cost with the cost of a replacement. If we do not have a dated manufacturer price for that model, we omit the battery path instead of guessing. Run the questionnaire on your iPhone 13 or iPhone 14 with the health figure from Settings if you have it — "I don't know" is stored and lowers confidence on purpose.

See the product pages for the figures, and how we work it out for the method.