📖 Food facts
Can You Make Mashed Potatoes Ahead of Time?
Two days in the refrigerator is the sweet spot. The trick is a looser mash going in, a gentle reheat, and a slow cooker used only for holding.
By Americanized · Edited by JP Lambiase · October 19, 2026
Yes, up to 2 days: America's Test Kitchen refrigerates its make-ahead mashed potatoes that long, well inside USDA's 3 to 4 day limit for leftovers. Make them looser than usual, reheat them covered until they reach 165°F, then hold them in a preheated slow cooker at 140°F or above. Don't reheat cold potatoes in the slow cooker itself.
How far ahead, and how to store them
USDA's Food Safety and Inspection Service (FSIS) says cooked leftovers keep 3 to 4 days in the refrigerator and should go in within 2 hours of cooking. Spread hot potatoes into shallow containers so they cool quickly, then cover them tightly.
Safety allows 4 days, but texture is the real limit. America's Test Kitchen (ATK) designed its make-ahead recipe for up to 2 days in the refrigerator, so for a Thursday dinner, Tuesday is the earliest to mash. It frees a burner on the day, and our Thanksgiving planner can fit it into the rest of your timeline.
Mash them loose, and gently
Potatoes keep absorbing liquid as they sit, so a mash that is perfect at dinner turns stiff after a night in the refrigerator. ATK's answer is extra dairy: its make-ahead version uses heavy cream instead of half-and-half and folds in a final cup of hot cream, so the mash is quite loose when it goes into the bowl.
Glue is a starch problem. ATK's Lan Lam explains that cooked starch granules swell, and overcooking or overmashing bursts too many cells and releases a sticky gel. A ricer or food mill is gentler than a masher. Our classic American mashed potatoes are riced, with melted butter stirred in before the half-and-half. For a make-ahead batch, our suggestion is to add warm dairy until the mash is a little looser than you would serve it.
Reheat without the glue
ATK reheats its chilled mash in the microwave in a bowl covered with plastic wrap poked with small holes, stirring halfway, about 14 minutes for a 5 pound batch. FSIS wants leftovers reheated to 165°F and covered while they heat, which keeps in moisture. Microwaves have cold spots, so check a few places with a thermometer.
If the reheated potatoes taste pasty, ATK's fix is fat: fold in about 1 tablespoon of melted butter per pound of potatoes, then another if needed. Stir gently, because beating hot potatoes is how they turn gluey in the first place.
Holding them in a slow cooker
FSIS is specific here: reheating leftovers in a slow cooker is not recommended. Reheat the potatoes on the stove, in the microwave or in the oven until they reach 165°F, then move them to a slow cooker that is already hot to keep them at 140°F or above for serving.
For texture, ATK holds freshly made slow cooker mashed potatoes on the warm or low setting for up to 2 hours, loosening them with a little hot water before serving. Keep a pot of turkey giblet pan gravy beside them, and find more styles in our mashed potatoes hub.
Questions people ask
Can you freeze mashed potatoes?
Yes. FSIS says frozen leftovers stay safe indefinitely and are best within 3 to 4 months. It also notes that slow freezing forms large ice crystals that can make cream separate, so freeze the potatoes quickly in shallow, airtight containers and thaw them in the refrigerator.
How long can mashed potatoes sit out on the table?
No more than 2 hours at room temperature, or 1 hour above 90°F, according to FSIS. After that, refrigerate them or throw them out.
Can I cook mashed potatoes in the slow cooker from the start?
Yes. ATK simmers sliced russets in the slow cooker, mashes them there and holds them on warm for up to 2 hours. That is a fresh batch rather than reheated leftovers, which is the case FSIS warns about.
Sources
- America's Test Kitchen, "Make-Ahead Mashed Potatoes" (December 19, 2011)
- Lan Lam, "Actually, It's Easy to Fix Gluey Mashed Potatoes", America's Test Kitchen (November 30, 2023)
- America's Test Kitchen, "Slow-Cooker Classic Mashed Potatoes" (September 15, 2017)
- USDA FSIS, "Slow Cookers and Food Safety" (Internet Archive copy, October 8, 2026)
- USDA FSIS, "Leftovers and Food Safety" (Internet Archive copy, October 8, 2026)
- USDA FSIS, "Freezing and Food Safety" (Internet Archive copy, October 4, 2026)
More food facts
Cook it
Classic American Mashed Potatoes
Whole russets simmered in their skins, peeled hot and riced, then stirred with melted butter first and warm half-and-half second for a fluffy, creamy holiday mash.
Garlic Mashed Potatoes
Rinsed russet cubes simmered in butter, half-and-half and a little water with a dozen cloves of garlic that were first cooked with a pinch of sugar until sticky and golden, then mashed with more butter.
Loaded Mashed Potatoes
Skin-on russets mashed with warm half-and-half and butter, then loaded like a baked potato with crisp bacon, cheddar, sour cream and chives.
Turkey Giblet Pan Gravy
Real gravy from the bird: a giblet broth made while the turkey roasts, a nutty brown roux, and the roasting pan deglazed with white wine so every browned bit ends up in the sauce.
Sweet Potato Casserole with Marshmallows
Sweet potatoes cooked down in butter and cream instead of water, mashed with a little cream cheese, then covered with halved marshmallows and baked in a hot oven until they puff and brown.