What a weekly shop really costs, and what splitting saves.

What we measure

A fixed basket of 30 everyday staples (23 national-brand items plus 7 fresh/commodity lines such as bananas, potatoes, chicken breast, beef mince, eggs, pasta and cooking oil), priced across the six largest UK online supermarkets: Tesco, Sainsbury’s, Asda, Morrisons, Ocado and Waitrose.

How products are matched

• Identical products are matched by barcode (EAN), the same Heinz, Lurpak or Cadbury at every store.
• Same brand, different pack (*), compared by unit price (per litre / kg). Applies this month to Coca-Cola.
• Equivalent product (†), where no single brand is stocked everywhere or the item is fresh, we compare each store’s standard own-label equivalent at the same size and quality tier.

Every price is individually verified

Every one of this month’s 180 prices (30 items × 6 stores) comes from the Shopsplit database, the same live pricing engine that powers the app, and was also checked directly against each retailer’s own website before publication. This isn’t a one-off audit: it’s the standard process behind every edition.

The three price views

Every figure on this page responds to the selector at the top, because there isn’t one honest answer to “what does this cost.” It depends on what you’re willing to sign up for:

• Shelf prices: the standard price with every discount stripped out. The cleanest like-for-like comparison, and the one least distorted by whatever each store happens to be promoting this week.
• + Promotions: shelf prices plus any publicly available promotion. No account, no card, no sign-up: if you walked in today, this is what you’d pay.
• + Loyalty prices: the above plus loyalty-card pricing. Assumes you hold a Tesco Clubcard, a Sainsbury’s Nectar card and an Ocado Smart Pass.

Conditional multi-buys

Conditional offers (“Any 2 for £5”, “Buy any 3 for £9”) are included and marked ‡ in the price table. The price shown is the per-item price assuming you buy the offer quantity. Buy a single unit and you pay the standard price instead. We include them because they’re real savings shoppers do take, but they’re flagged so the figure is never mistaken for a single-unit price.

Loyalty-card pricing

Loyalty prices are marked ◆ and are only counted in the + Loyalty prices view. This month, three of the six supermarkets used them: Tesco Clubcard on 9 of the 30 items, Sainsbury’s Nectar on 10, and Ocado Smart Pass on 2. We checked Asda, Morrisons and Waitrose individually and found no member-only pricing on any basket item; their discounts were open to all shoppers. Asda Rewards pays into a cashpot rather than reducing the price at the till, so it isn’t treated as a price cut here.

How the split is calculated

We test every possible combination of stores and pick the true optimum: each item bought from whichever chosen store is cheapest.

Caveats

• Excludes delivery fees and the time/cost of ordering from more than one store.
• Aldi is not included: its limited online range makes a like-for-like 30-item basket impossible.
• Own-label and fresh lines are equivalent-product comparisons, not identical products.
• Conditional-multibuy prices (‡) assume the offer quantity is bought (see above).
• Loyalty prices (◆) require an account with that retailer, and only appear in the + Loyalty prices view.
• “Cheapest” / “priciest” refer to the lowest / highest 30-item total; stores can be closely clustered, so the ranking can shift month to month.
• A point-in-time snapshot, not a continuous average.