Groceries · 7 minute read
Can Costco save you money in the long term?
Bulk buying looks cheap on the shelf. Whether it is cheap in your kitchen depends on the membership fee, what you actually use up, and how far you drive to get there.
Published 30/09/2026
Start with the fee, not the trolley
Costco charges an annual membership. Before you join, divide that fee by the number of trips you will realistically make in a year. If you only go four times, each trip starts with a sizeable surcharge before you buy anything. Check the current fee on Costco's own site, as it changes.
Compare the unit price, not the pack price
A giant pack is only a deal if the price per 100g, per litre or per wash beats Aldi or Lidl own-label. Write down unit prices for the ten things you buy most and compare them. Toilet roll, washing tablets, rice, oats, tinned tomatoes and frozen chicken are where bulk often wins. Fresh fruit, salad and bread often lose, because they go off first.
Know the pack sizes before you go
Warehouse packs are far bigger than supermarket ones: multi-kilo sacks of rice, big trays of meat, catering tubs of sauces, dozens of eggs, and cases of tins or drinks. Look at the size on the label and ask how many weeks it will take your household to finish it. A simple rule: if you can't eat it before it goes off, don't buy it, however good the unit price looks.
Check the shelf life on big items
Dry rice, pasta, oats, tins, toilet roll and cleaning products keep for months, so buying big is low risk. Oils, nuts, flour and coffee go stale or rancid sooner once opened. Fresh meat, dairy, bread and fruit last days, not weeks. Check the best before or use by date in the warehouse and compare it with how fast you get through that item at home.
A deep freezer changes the maths
Bulk meat, bread, frozen veg and batch-cooked meals only pay off if you can freeze them straight away. With a chest or upright freezer, you can split a big meat pack into meal-sized bags on the day you buy it, label them, and use them over the following weeks. Without freezer space, most fresh bulk buys end up in the bin. Remember a freezer adds to your electricity bill, so it works best when it stays full.
Add fuel and waste
Warehouses are usually out of town, so add fuel or parking to every trip. And every item you throw away wipes out part of the saving on the rest.
Split it with someone
Sharing a membership trip and splitting big packs with family, friends or a neighbour gets you the unit price without the waste or the storage problem.
The verdict
Costco can pay off for bigger households with storage space who stick to a list of long-life staples. For small households, or anyone who shops on impulse, a discounter's own-label range is usually the safer bet.
See this week's Aldi vs Tesco vs Asda basketSources
General information, not personal financial advice. Check current prices and rules with the original source.