The first thing you should always do if your card declines at the supermarket checkout

Most of us have had that awkward moment where we've gone to pay for something at the checkout and our card has declined.

For many it's a case of not moving money over to another account before the shop or pulling the wrong card out of your wallet.

But for a staggering 20 per cent of Aussies – the equivalent of 4.2 million people – their card has declined because they just don't have the money left between paychecks.

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According to research from Finder, six per cent of those have ended up putting the groceries on their credit card instead, while another seven per cent have returned some items and seven per cent have abandoned their grocery shop altogether.

Rebecca Pike from Finder told 9honey Money that this is becoming more common as the cost of living crisis continues.

"Things just are costing too much, and when you have maybe a price in your head of what your groceries are going to cost and then you get to the checkout and you realise you haven't quite budgeted that well or things have added up more than you expected – I think that's what's happening here, and it's heartbreaking if you can't get these few things that you need," she says.

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When your card declines and you can't get those few grocery items you need to get through the rest of the week, you might start to panic about what to do.

Pike encourages anyone who goes through this to take a deep breath before deciding your next move.

Being at the checkout you may feel rushed to make a decision, but you don't have to act quickly and can even ask the staff for help while you make a decision.

"Really look at what you've got there and [think] what do you desperately need? You know, if you need to feed the kids... So pull up your banking app, check your situation and just do a quick calculation," Pike says.

"What 100 per cent do you absolutely need and then just start putting things aside. Checkout staff are great, they will take things back for you, they'll put it aside for you."

Credit cards might seem like the perfect option in this situation but if you're continuously relying on them it can make things worse.

"Some people have credit cards and they have wonderful budgeting skills with it – they pay it off every month. But if you're really struggling with those costs, if you're living paycheck to paycheck and you're running out of money, then a credit card is just gonna make things harder further down the road," Pike says.

With the cost of living showing no sign of easing we're having to rely on being organised, planning ahead and using tips and tricks to make ends meet.

One forgotten tip Pike recommends is looking at lower and higher shelves for more affordable items instead of the middle section where our eyes are drawn to.

"The cheapest stuff is is often at the bottom or right at the top – the middle stuff is where they where they want you to buy, so that's all the expensive stuff," she says.

While some sales can be helpful in allowing us to meet budget, Pike encourages you to consider whether that item really is the cheapest option.

"Look at the unit price. Don't get sucked in because something's $2 and something else is $3 because it might be that the $2 thing is much smaller and you'll run out faster and you'll need to pay it again sooner."

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And to make sure you have something set aside for those times when you run out of cash before the next payday, start putting away a little bit of money regularly as an emergency fund.

"Even just $5 or $10 dollars a week [helps], because at the end of that month I imagine that people aren't falling short by $100, they're falling short by $10, $20, $30 at the supermarket checkout. So if you have that bit set aside, then very often you might go, 'OK, I can just about make it if I use this emergency cash'," Pike says.

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