What Temperature Should a Freezer Be?

The standard temperature for commercial freezers in the UK is -18°C or below. This temperature is recognised internationally by the Codex Alimentarius and is referenced in UK food safety guidance. At -18°C, bacterial growth is effectively halted, though it is important to understand that freezing does not kill bacteria — it simply prevents them from multiplying. Once food is thawed, any bacteria present will become active again, which is why thawing procedures and subsequent cooking temperatures are equally important. The Quick Frozen Foodstuffs Regulations 1990 (as retained in UK law) specifically require that quick-frozen foodstuffs are stored at -18°C or colder, with a permitted brief tolerance of up to -15°C during transport and local distribution. For your own frozen products, the FSA guidance is clear that -18°C is the target. Most commercial freezers should be set slightly colder than -18°C (typically -20°C to -22°C) to account for temperature rises when the door is opened. As with fridges, freezer temperatures should be monitored and recorded as part of your food safety management system. Check and log temperatures at least once daily. If a freezer fails or rises above -18°C for an extended period, you need to assess whether the food is still safe. Food that has partially thawed and been refrozen can suffer from both quality degradation and potential safety issues. If food has thawed to above 5°C, it should be treated as chilled food and used within its chilled shelf life, or discarded if that period has been exceeded.