Australia's most financially savvy single mum on how she cuts her grocery bill in half.

Grocery shopping can very quickly get out of hand.

One minute, you’re shopping for some milk and 30 seconds later you’re heading to the checkout with four packets of chocolate biscuits, a punnet of lychees and some tinned caviar “just in case”.

It’s not ideal – and can quickly eat into your weekly budget and savings.

Financial expert and creator of the Sugar Mumma YouTube channel Canna Campbell shared her best tips to reduce the cost of your weekly supermarket shop on the latest episode of I Don’t Know How She Does It.

Listen: How to cut the cost of your weekly grocery shop. Post continues after audio.

Not only are they simple AND effective, they’re also a sure fire way to prevent those impulse buys.

1.Shop online.

Anything that involves not leaving your sofa? Count us in.

“Doing your grocery bill online actually gives you a lot more control. When we’re in a supermarket, it’s not until we get to the checkout, we go ‘Uh! WOW, how did that add up’,” says Campbell.

“And it’s too awkward and we’re too time-poor to go, ‘I’m going to put a few things back’ as it’s all bagged up and ready to go.When you shop online, you can actually see ‘Wow, this is adding up. Maybe I won’t get that many punnets of organic blueberries’ and you can kind of cut it down, control how it’s all adding up.”

While there is an additional delivery fee, Campbell says it's often worth it.

"And I know people say 'Hang on, you've got to pay the delivery fee' but yes, you do but its like $11. You are paying $11 but someone is going to the supermarket, walking up the aisles, putting stuff into the bag, bag into car then into your house. So that $11 is a great investment."

2. Go with a plan.

And by that we mean a detailed list of everything you need for the week. Do not stray off it - even for those delicious looking treats currently on special.

"Check what ingredients you already have at home [so you don't double up]. It's so easily done to buy what you've already got in," she says.

Just filmed "How to start your share portfolio!" on Heron Island...publishing next #Monday xCC

A photo posted by SugarMammaTV (@sugarmamma.tv) on Nov 26, 2016 at 4:58pm PST

3. Work out your meals for the week.

Allocate some time the night before your weekly shop to work out exactly what you'll be eating in the week ahead - taking into account any nights you're out too.

"It's a great way to stop you adding on all the little things and wondering what you are having for dinner and adding stuff, that dramatically cuts down the bill," Campbell says.

4. Cook once, eat twice.

Future you will thank you for it.

"Cook a large meal that you know you can put in the freezer for another day or times when you need an extra meal or take to lunch so you can save some money then," advises Campbell.

Lean, healthy option from @mealprepslo Ingredients: Chicken: lightly brush with olive oil ground pepper dried basil dried parsley heat oven at 400 for 20-25min Sweet potatoes: slice at desiered thickness pepper if wanted heat oven at 400 for 25-30min fresh green beans: lightly cooked #mealprepsunday #mealprep #mealprepsociety #mealprepping #mealprepideas #food

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5. Have some meat-free nights.

Ditch the beef and experiment with some delicious vegetarian dishes.

"Meat is expensive. Have some meat free nights, your body is going to feel the benefit of that," says Campbell.

6. Go simple.

It's still delicious - and also easier and quicker to cook.

"There are a whole range of cooking books out there to cook with less. Obviously the simpler your meals, the cheaper they will be and the bills are going to come down," she says.

Image: iStock

7. Get to know your supermarket.

Pay close attention to the cost of things you buy weekly to learn when they're likely to go on special. Generally, stores run on a 12 week cycle.

"[Learn] when things go on special, when fresh deliveries come in as that's when they need to clear stock. All these little things really do add up," says Campbell.

8. Use cash.

Ditch the credit card, and your bank account will thank you.

"Don't use credit cards or paywave, you're not present - you just swipe it and you think 'It's just a $4 coffee' but doing that five times a week really does add up and eat into the cash out of your account," says Campbell.

"Put cash in your wallet and when possible pay for things in cash if you find your whittling through all your money."

Listen: The full episode of IDKHSDI is packed with financial savvy tips and hacks. 

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