I’m a supermarket expert – you’ve been putting your shopping list together all wrong

WRITING a list before your big weekly shop can help you save money - but putting it together wrong could actually cost you thousands.

Being prepared before you head to the supermarket is vital, but five shopping list mistakes could easily be costing you £190 a month.

That's money many households can't afford to waste during a cost of living crisis, as runaway inflation is driving food prices up.

Shoppers are facing forking out £533 more a year just to fill the fridge up.

The Sun asked supermarket expert Charlotte Jessop her top tips for making a money-saving list - and the mistakes to avoid.

She runs the finance blog  , and saves herself hundreds of pounds a month using clever shopping tricks.

Listing brands - lose £20 a month

We all know and love big brands - but are often much more expensive than supermarket-own ranges.

Already pricey brands are getting even more expensive - Heinz has hiked prices by 3.8 percentage points.

While the bosses of companies which make Marmite, Magnums and KitKats have all warned of price increases.

Charlotte said: " If you are automatically buying the top brands because you haven't stopped to try out the cheaper supermarket own alternatives then you could be overspending by £20 a month."

If you're too attached to your branded biscuits or tins, then look at other items to "down-shift" on - including your laundry detergent or cleaning products.

Making lists TOO frequently - lose £20 a month

If you find yourself popping lists together for your groceries for daily shops, it's likely you are overspending.

Popping to the shops more frequently leaves you "open to temptations and marketing", Charlotte said.

It means you're likely to come out with more items than you really needed.

Plus, as you're shopping for small items, you won't be able to bulk buy items, which is often where the real savings come in.

Remember to check for prices per kilogram on larger items to make sure you're getting the best deal you can.

"It might feel more convenient to do smaller daily shops but it could cost you £20 more a month," Charlotte said.

Forgetting about apps - lose over £50 a month

When you're sitting down to write your list, make sure to have shopping discount and cashback apps open.

It's worth investigating which groceries are listed on apps like Shopmium, CheckoutSmart, GreenJinn and ClickSnap.

These sites work by promising to earn you money back on your shopping - they agree offers with retailers, and pass these on to customers.

You need to sign up to the apps - which are free to do so through Google Play or the App store.

Once you've got yourself an account, you can scroll through the deals listed on the site.

You can pick up items at big supermarkets like Tesco and Sainsbury's.

Simply go to the store, buy the product under offer, take a picture of your receipt, upload it to the app and you can get your cash back.

Make sure to jot down all the items you need from these sites, Charlotte said.

"They are definitely worth investigating before you head to the shops, it could save you £50 a month," she added.

Not making a list at ALL - lose over £100 a month

Time-strapped shoppers may be tempted just to head to the shops without writing a list beforehand.

It means that without checking the fridge to see what's in, you're playing a guessing game at the shops over what you actually need.

This could see you massively overspend, Charlotte said.

"Planning your meals can save you huge amounts of money and is probably the easiest way to reduce your grocery spends - and it has the most impact money-wise," Charlotte said.

"It could be costing you over £100 a month."

You're more likely to get sucked into picking up promotions you don't actually need.

You might pick up food that you already have in the fridge because you've forgotten about it.

That could mean throwing away perfectly good food - this alone is costing households £800 a year.

Sticking to a list means that you're just sticking to your essential supplies - and keeping money in your pocket.