Comparing Payment Methods
There are two families of payment methods. Cash, checks, and debit cards spend money you already have — the money leaves your pocket or your bank account, and the transaction is over. Credit cards and store credit spend borrowed money, which you must pay back — with interest if you pay late.
That one distinction decides everything. The same item can end up costing different totals depending on how you pay for it, so the comparison skill is simple: figure out each method's true total, then line them up.
Your money versus borrowed money
Cash and checks draw directly on money you own. A debit card does the same thing electronically — it pulls money straight from your own bank account. With all three, the total cost of an item is just its price. No interest is ever possible, because nothing was borrowed.
A credit card spends the bank's money. You are expected to pay the bank back, and if you pay late, the bank charges interest on what you owe. Store credit works the same way, except the store is the lender — and store credit usually carries the highest interest rate of all.
Compare true totals, not price tags
To compare methods, compute what each one actually costs in total. For cash, check, and debit that is the price. For a credit plan, either total the payments — — or add the interest to the price using .
Take a $500 TV. Cash or debit: $500. A credit card charging 9% simple interest for the year adds , for a total of $545. Store credit at 14% adds $70, for a total of $570. Same TV, three different totals — and the gap is pure interest. The table lines up all three totals side by side.
A small monthly payment can disguise an expensive plan. Paying $22 a month for a $240 bike sounds cheap, but 12 of those payments total . Always multiply out the whole plan before deciding it's a deal.
Worked examples
Example 1: read a table of totals
Each method pays for the same $300 tablet: cash $300, debit $300, credit card $324, store credit $348. How much more does store credit cost than cash?
Answer: Store credit costs $48 more than cash.
Example 2: store credit versus cash
A desk costs $360. Store credit charges $34 a month for 12 months. How much more does store credit cost than paying cash?
Answer: Store credit costs $48 more than paying cash.
Example 3: interest stated as a rate
A jacket costs $240. Store credit charges 15% simple interest for 1 year. How much more is store credit than paying cash?
Answer: Store credit costs $36 more — the extra is exactly the interest.
Try one yourself
Common questions
What is the difference between a debit card and a credit card?
A debit card pulls money straight from your own bank account — you are spending money you already have. A credit card spends the bank's money, which you must pay back, and paying late means owing interest on top.
Which payment methods can never charge interest?
Cash, checks, and debit cards. All three spend only money you already own, so there is nothing borrowed for interest to grow on. The total cost with any of them is just the price.
Why does the same item cost different amounts with different methods?
Interest. The price is the same for everyone, but borrowed-money methods add interest on top. The gap between a credit total and the cash price is exactly the interest charged.
Is store credit worse than a regular credit card?
Usually. Store credit tends to carry a higher interest rate than a regular credit card, so its total for the same item is usually the highest of all the methods. Check the rate — or the totals — rather than assuming.
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