That will be £42.40,’ says the checkout assistant as I pack my Tesco shopping into bags.

It’s more than I’m expecting but, as everything seems more expensive these days, I don’t question it.

I scan my Clubcard as I go to pay and suddenly the price drops by nearly a third to a total of £29.22.

Dodgy discounts: This basket of shopping costs an average of 45% more at Tescos than at the other Big Four supermarkets if bought without a Clubcard

Discounts that are not so good: If you don’t have a Clubcard, this basket of shopping will cost you 45% more at Tescos.

The assistant smiles when I say that my surprise was expressed. ‘You don’t get any of the deals without the Clubcard any more. People really regret it when they don’t use one,’ she says.

As I leave with my trolley, I can’t help but think this doesn’t seem fair.

While customers should be rewarded with benefits if they use a loyalty card and share their shopping data with retailers, they shouldn’t be penalised if they choose not to, says consumer expert Martyn James.

‘Any business with a loyalty card should give people the option of opting out of their data being collected without losing discounts,’ he adds.

Tesco Clubcards have been used by over 20 million Britons. These cards allow customers to earn points, which can be converted into cash-off vouchers.

In return, Tesco gets the details of what you buy, how much you spend and how often you shop — information vital to the retailer in helping it to understand its customer base and maximise its profits.

In fact, this data is so valuable that last month Tesco announced it was now a ‘media owner’ and would use the information it receives from Clubcard shoppers to sell advertising space to brands.

It is doing this via a ‘media and insight platform’ operated by its wholly owned subsidiary Dunnhumby, a London-based ‘consumer data science’ specialist.

On the firm’s website, a section aimed at attracting advertisers to the Tesco scheme explains that it can use Clubcard data to ‘build an exact profile of your best customers, and what matters to them most’.

Furthermore, it says it can ‘target customers from sofa to store, wherever they are and whatever their mindset’.

Brands can also be assured that it tracks what customers buy when they view specific advertising, in order to make sure they have an influence on how we purchase.

Tesco will sell advertising space in stores, on its Scan as you Shop app and website; via marketing emails and on Clubcard voucher mail letters. This allows shoppers to be targeted with offers and coupons when they get their vouchers.

But what if you don’t want the supermarket to profile you and use that information to target you with advertising?

After seeing the extra costs, I almost left my shopping cart at the till. 

Stephanie Oram's £10 meal-for-two deal would cost her £18 without a Clubcard

Stephanie Oram’s £10 meal-for-two deal would cost her £18 without a Clubcard

Author Stephanie Oram almost had to walk away from a Tesco till when she discovered a £10 meal-for-two deal would actually cost £18 without a Clubcard.

However, a fellow shopper in the queue overheard her dilemma at the last minute and let her borrow his card so she could get the £10 deal.

Stephanie, pictured, who lives in Blackpool, Lancashire, had left her house with just a £10 note in her pocket as she knew what she wanted to buy.

She realized she forgot her Clubcard when she made ranch steaks, orange dessert, chips, and wine.

The cashier then told her that without it she would have to pay £18 for the meal deal. As she considered what to do, a queue built up behind her — until finally the other customer stepped in to offer his help.

Stephanie said: ‘The queue was building and the colour in my face was rising.

‘I was getting ready to put everything back when a man next to me offered to let me use his card. ‘It was a win-win — I got the discount and he got the points.’ 

Stephanie (51 years old) said she hadn’t noticed Clubcard discount codes in stores but is now realizing that her shopping experience was much more costly than expected because she didn’t have her card.

She said: ‘I think the new system is a bit unfair because you are paying so much more if you do not have the card. But it is clearly to encourage loyalty.’

Previously at Tesco, you could simply opt not to use a Clubcard if you didn’t want to share your data. You would miss out on earning points.

But in 2019, the supermarket introduced Clubcard Prices — a system where discounts are available only to Clubcard shoppers. This is now available nationwide. To access these special offers, you will need a Clubcard.

Without a Clubcard you’re likely to be out of pocket, as the standard prices of many items are surprisingly high.

For example, a 500g tub of Lurpak slightly salted spread costs £2.75 at Tesco with a Clubcard but £4 without. 

And for a 100g jar of Nescafe Azera Americano coffee, you would pay more than double at £5.49 without a Clubcard, compared to £2.74 with one.

My 15 items cost £29.22 with a Clubcard; £42.40 without. And when I looked up how much the same basket of goods cost at other supermarkets, I found I could have bought them for a total of £32.07 at Asda, £34.58 at Morrisons and £35.30 at Sainsbury’s.

This means that Tesco’s prices for items without Clubcard are about 25% higher than those charged at the Big Four supermarkets.

However, the Clubcard did give me a good deal on my shop — it was about 14 per cent cheaper to buy the goods at Tesco with a card than the average cost across its competitors of £33.98.

My shopping experience would have been 45 percent more if my credit card had not been scanned or I chose to skip it.

Tesco gets information from your Clubcard about what you buy, how much you spend and how often you shop

Tesco Clubcards have been used by over 20 million Britons. These cards allow customers to earn points, which can be used for money-off vouchers

This was just a sample of 4,500 Tesco products included in their deals. Comparatively to other major supermarkets 60 percent of my items were higher or more expensive than when I was shopping with a Clubcard.

‘Customers shouldn’t have to pay a premium to keep their data private,’ says James Daley, of consumer group Fairer Finance. ‘You used to be awarded benefits for sacrificing your data. Now it looks like you have to pay extra if you value your privacy.’

James Walker, of consumer data action website Rightly, describes the situation as ‘daylight robbery’. He says: ‘Tesco has recognised the value of the personal information it holds on Clubcard customers. The downside for the customer is that they are subjected to bias and the overpricing of services.’

Tesco claims customers can modify their marketing preferences through their account. Targeted marketing isn’t a requirement to benefit from Clubcard offers and points.

But when I logged into my account on the Tesco website, I could only find an option to opt out of receiving ‘marketing offers or promotions from Tesco stores by email, text message, phone and post’. Targeted marketing is not mentioned in the store, on the website or via smartphone apps.

Loyalty card holders may also receive special discounts from other retailers. Superdrug has a rotating selection of deals only available to its Health & Beautycard holders.

And in September, Sainsbury’s introduced a scheme called My Nectar Prices, which offers discounts on selected goods to those who have its Nectar card and use its SmartShop phone app to shop in store.

However, unlike Tesco’s loyalty cards, customers can still benefit from discounts and other offers at both stores.

A spokesman for Tesco says: ‘We make it easy for customers to make choices about the data they share, and you can have a Clubcard and benefit from Clubcard Prices while choosing not to receive targeted marketing.

‘We only ever use data customers have agreed to share with Tesco, which allows us to personalise our offers. So, for example, if you’re looking for a bottle of red wine for Christmas and there’s a great offer on the wine you usually buy, it’s helpful for us to let you know.’

Expensive to leave a home card 

Andy Coley used to shop at Tesco for many years, but now he avoids it because he must pay more if his Clubcard is lost.

He says: ‘It feels like a first-class and second-class pricing system, where only some people are rewarded. People who lose their cards feel like they’re throwing away money.

‘Since Covid we all have enough things to worry about when visiting a supermarket such as keeping safe.’

¿Price-attacked¿: Andy Coley with his daughter Megan, four

‘Price-attacked’: Andy Coley with his daughter Megan, four

Mindset resilience trainer has his Clubcard in a ring that he keeps with his car keys. He doesn’t always have it with him.

And he does not have the store’s smartphone app.

He estimated that he lost out on around £50 of discounts during one big shop because he did not have his Clubcard. Andy, 45, of Lewisham, south-east London, says he has also noticed that Sainsbury’s is introducing this type of pricing for Nectar card customers.

A recent offer on a bag of nectarines cost £1.23 with a Nectar card compared to £1.50 without.

He says: ‘You feel like you have missed out when you should not have. Unless I need something specific from Tesco I will not shop there any more as I do not like being price-attacked.’  

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