How Long Does Kefir Last?
Storage method
Kefir — fermented milk — refrigerator, from date of purchase
1 week in the refrigerator
- Refrigerator at or below 40 °F (4 °C)
- Applies from date of purchase · fermented milk
Pick a valid date to calculate the recommended use-by window.
Source: USDA FSIS FoodKeeper (v128, snapshot 2026-07-24) · About this data · Report an issue
FoodStorageCheck — official USDA FoodKeeper guidance · foodstoragecheck.com
All official guidance for kefir
Every storage entry the USDA FoodKeeper dataset lists for this food, exactly as published (v128, snapshot 2026-07-24). “No official duration listed” means the source does not provide a number for that combination — not that the food lasts forever.
| Where | Condition | Official time |
|---|---|---|
| Refrigerator | from date of purchase | 1 week |
| Refrigerator | after opening | 1 to 2 days |
| Freezer | general guideline | Not recommended |
Common questions about kefir
- How long does kefir last in the refrigerator?
- 1 week in the refrigerator, counted from the date of purchase, per the USDA FSIS FoodKeeper dataset. Times assume a refrigerator at or below 40 °F (4 °C).
- Can you freeze kefir?
- The USDA FoodKeeper dataset lists this storage method as not recommended for kefir.
- How long does kefir last after opening?
- Once opened — refrigerator: 1 to 2 days, per the USDA FSIS FoodKeeper dataset.
Two reminders that apply here
Keep the fridge at 40 °F (4 °C) or below.Refrigerator times in this dataset assume a refrigerator held at or below 40 °F. An appliance thermometer is the reliable way to check.
The two-hour rule.Perishable food left at room temperature for more than 2 hours (1 hour above 90 °F / 32 °C) should be discarded, per FoodSafety.gov. Storage windows assume food was refrigerated promptly.