How long does Buttermilk last in the fridge?
Turning the range into a date
Buttermilk keeps 1 week sealed in the fridge. The window here is 2 weeks, short enough that the day it went in is worth writing down.
- In the freezerUse by3 months after the day you bought it
- Unopened · in the fridgeUse by1 week to 2 weeks after the day you bought it
Freezing changes the unit, not just the number
Freezing does not just add time to this item, it changes the unit the answer is written in: 2 weeks in the sealed fridge against 3 months in the freezer, 6.4 times longer, months in place of weeks. On the same shelf it sits 12 of 29, between Dips, sour cream based at 2 weeks and Whipped topping at 2 weeks.
Every storage figure the USDA publishes for this item
The USDA rates this item cold or frozen and never at room temperature: no pantry figure exists for it, as for 222 of the 466 foods in the data that get no pantry time at all.
- In the freezer3 months
- Unopened · in the fridge1 week to 2 weeks
Is it still safe to eat, or just past its best?
The answer at the top of this page reads 1 week to 2 weeks in the fridge. What decides that is the food: the source files Buttermilk under Dairy Products & Eggs, a heading it keeps for perishable food. Past it, it is not safe to eat: throw it out without tasting, because bacteria build up while food still looks and smells fine.
The figure in the freezer here is a quality window. The same page carries windows of more than one kind, so which sentence applies depends on which row you are reading, not on the food. Held at 0 °F food stays safe for as long as it stays frozen, which is why a freezer figure counts as quality on this site whatever the food is. Every figure assumes the food was sound when you stored it, that your refrigerator holds 40 °F or below and your freezer 0 °F or below, and that the package was handled normally.
It is past the date. Now what?
Say the calculator above puts Buttermilk past its 1 week to 2 weeks in the fridge window, or the container sat out on the counter overnight. Throw the container out without tasting it, and count any hours it already spent out of the refrigerator as part of that window rather than on top of it.
The USDA's limit for perishable food standing at room temperature is 2 hours, or 1 hour when the kitchen is above 90 °F, and that clock runs whatever the storage figure says. Freezing stops the clock but does not turn it back: food already past its window is not rescued by putting it in the freezer. The FoodKeeper entry this page is built from prints storage times and nothing else, so anything past them here is USDA and FSIS guidance rather than a figure from the source. The whole rule, including the cases the source does not cover, is set out under what to do when the date has passed.
Is that a long time?
8 items in the Dairy Products & Eggs list keep exactly as long as this item, 2 weeks, so they all share place 12 of 29 rather than being put in an order the data does not support. Among the 340 foods the USDA also gives a refrigerator figure, it keeps longer than 53% of them.
Items that behave the same way
All 5 of the 6 items nearest this item keep exactly as long as it does, 2 weeks, so the ranking around it is a tie rather than an order.
Products the USDA rates in the same places
This is a common shape of record: 52 of the 466 products are rated in the same places, freezer from the day of purchase and refrigerator from the day of purchase, and 7 of the nine slots are left blank on all of them. Sorted by how close their windows are to this one, the nearest are Cabbage, Celery and Leeks, and the rest of that group is what the list below draws on. Of the ones shown, none keeps longer than this one does.
- Cabbage1 week sealed in the fridge
- Celery1 week sealed in the fridge
- Leeks1 week sealed in the fridge
- Peppers4 days sealed in the fridge
- Turnips2 weeks sealed in the fridge
- Shucked clams3 days sealed in the fridge
- Lemongrass7 days sealed in the fridge
- Corned beef5 days sealed in the fridge
The rest of the Dairy Products & Eggs shelf
The USDA puts this product on the Dairy Products & Eggs shelf together with 28 others, and 11 of them keep longer outside the freezer. The shelf runs from Powdered milk at 5 years down to Pudding at 2 days. Nearest this product by window are Cottage cheese, Cream cheese and Dips, which is the order the list below is printed in. The order counts the longest window outside the freezer, so this item sits here at 2 weeks rather than at the 1 week sealed in the fridge its own answer prints.
- Cottage cheese2 weeks1 week in the fridge once opened
- Cream cheese2 weeks2 weeks sealed in the fridge
- Dips2 weeks2 weeks sealed in the fridge
- Whipped topping2 weeks2 weeks sealed in the fridge
- Yogurt2 weeks1 week sealed in the fridge
- Ricotta2 weeks1 week in the fridge once opened
- Cheese Curds2 weeks2 weeks in the fridge
- Soy milk10 days7 days in the fridge once opened
If it has to keep longer than this
If it has to keep longer than 2 weeks, the Dairy Products & Eggs aisle gives 10 products that hold at least twice as long outside the freezer. The smallest step up is Whipped cream at 4 weeks against this one's 2 weeks; after it come Pimento cheese, Eggs and Butter. They are printed below in the order the step gets bigger, not alphabetically. In the other direction, 5 entries in the category keep half as long or less, Kefir and Eggnog among them. The largest step the category offers is Powdered milk at 5 years.
- Whipped cream4 weeks3 weeks sealed in the fridge
- Pimento cheese4 weeks4 weeks in the fridge once opened
- Eggs5 weeks3 weeks sealed in the fridge
- Butter2 months1 month sealed in the fridge
- Vegan Cheddar Cheese4 months3 days in the fridge once opened
- String Cheese5 months5 months sealed in the fridge
- Margarine6 months6 months sealed in the fridge
- Nacho cheese2 years2 weeks in the fridge once opened
The record this page is built from
This page is built from a single FoodKeeper row, record 2 — the source’s own number for it, not a position — one of the 661 rows in the snapshot. That row fills 2 of the nine storage slots with a time, and the binding figure on it is printed by the source in weeks, which is the unit this page keeps rather than converting it to days. Every figure here comes from one fixed snapshot, USDA FoodKeeper, retrieved 1 September 2026, and is not refreshed page by page.
Where these numbers come from
How long does this food keep in the refrigerator, in the freezer, in the pantry? Can you freeze it, and how much of its shelf life is left once the package is open? Every answer on this page is the USDA’s own published figure, one of the 9 it keeps per food, and never an estimate of ours.
Every range on this page is published by the USDA FoodKeeper and reproduced unchanged. The multipliers, the rankings, the percentages and the dates are ours, computed from those ranges. Where the source gives a span such as 3 to 5 weeks, comparisons use the upper figure, and the full span is always printed.
Rankings cover only the items the USDA gives a usable figure for, and identical ranges share a place rather than being ordered arbitrarily. Neighbors are chosen by nearest storage time within the same category, never alphabetically: two foods filed next to each other by name usually have nothing to do with each other. The freezer is excluded from ranking because it flattens almost everything.
Where the USDA lists several kinds under one name, they share one page here and every kind keeps its own windows: the source prints them as separate rows, and a page that merged them would be inventing a figure the source never published. Comparisons and the place in the category are computed for the kind the plain name means — the shell egg for eggs, the can for tuna — which is settled name by name rather than by the order the source lists its rows in, and the page names it. Where the plain name means no single kind, the page prints no single figure at all and lists the kinds instead.
Source: USDA FoodKeeper, retrieved 1 September 2026. This site computes every comparison on this page and takes responsibility for it. Found a figure that does not match the source? Tell us on the contact page, with the page and the row — the parsing is mechanical, so a mismatch is our bug and we want it. How the whole site is built, which figures are ours and where the source can be checked is on the method page.
KeepsUntil is an independent reference built on public USDA data. It is not affiliated with, endorsed by, or connected to the U.S. Department of Agriculture or the Food and Drug Administration. Whether a given window is a safety limit or a quality window is stated on the page that prints it.