How much should you borrow?
Start from the payment, not the amount. How to size a loan against your worst month rather than an average one, why the approved amount is not the right amount, and what common loan sizes actually cost.
Borrowing basics6 min readUpdated 15 September 2026By the MDG Lending Team
The short version
- Decide the payment you can sustain first, then work back to the amount.
- Test the payment against your worst month in the last year, not a typical one.
- Finance charges scale with the amount, so borrowing 20% less costs roughly 20% less.
- Take the longer term and overpay in good months. There is no prepayment penalty here.
Start from the payment, not the amount
Almost everyone does this the wrong way round: decide the amount, then discover the payment. Reversing it produces smaller loans, fewer missed payments and less interest paid, because the constraint you actually live with is the monthly payment, not the sum.
The test is not whether the payment fits a normal month. It is whether it fits your worst month in the last year, the one with the car repair and the higher energy bill in it. If it only works in a good month, it does not work.
Three numbers to write down first
- What actually reaches your account in a quiet month.
- What leaves it before you have any choice: rent, utilities, transport, food, existing payments.
- What is left. A new loan payment has to sit inside that, with room to spare.
What common amounts actually cost
The finance charge column is the one to look at when deciding whether the problem is worth solving this way.
| Amount | Representative APR | Term | Monthly payment | Finance charge | Total repaid |
|---|---|---|---|---|---|
| $1,000 | 29.99% | 12 months | $97.48 | $169.76 | $1,169.76 |
| $2,000 | 29.99% | 18 months | $139.33 | $507.94 | $2,507.94 |
| $3,000 | 24.99% | 24 months | $160.10 | $842.40 | $3,842.40 |
Every amount and term we offer is laid out on our loan amounts page, and you can model your own on the calculator.
Four questions that size a loan properly
Answer these honestly and the number usually answers itself.
What does the problem cost, exactly?
Get the quote first. Borrowing a round number because it sounds tidy is how people end up paying interest on $1,000 to fix an $840 problem.
Can I cover part of it myself?
Every dollar you do not borrow removes its share of the finance charge. Part-funding is not failure, it is the cheapest move available.
Could I make this payment in a bad month?
If not, take a longer term rather than a bigger risk. A payment you always meet costs less than one you sometimes miss.
Is the finance charge worth it?
Put the dollar figure next to the problem. Sometimes it obviously is. Sometimes seeing it changes the decision, which is the point.
Why the approved amount is not the right amount
An approval limit describes what a lender will do, not what you should do.
- Borrow the figure that fixes the problem, not the figure on the offer.
- Finance charges scale almost directly with the amount, so borrowing 20% less costs roughly 20% less.
- A smaller loan is also more likely to be approved in the first place.
- Leftover borrowed money tends to get spent, and then repaid with interest.
Take the longer term, then overpay
There is no prepayment penalty here, so the safest structure is a term whose payment you could meet in your worst month, with extra payments whenever a good month arrives. You get the safety of the long schedule and most of the saving of the short one.
Questions on this topic
How much should I borrow?
The exact amount that solves the problem, sized so the payment fits your worst recent month rather than an average one. Approval limits describe what a lender will lend, not what you should take.
Is it better to borrow more and pay it off faster?
No. Finance charges scale with the amount, so borrowing more costs more regardless of how quickly you repay. Borrow less and take a comfortable term instead.
Should I choose the shortest term I can afford?
Choose the term whose payment you could meet in a bad month, then overpay in good months. There is no prepayment penalty, so you capture most of the saving without the risk.
What if I can only cover part of the cost myself?
Then borrow only the difference. Every dollar you do not borrow removes its share of the finance charge, and a smaller request is also more likely to be approved.
How do I know if a finance charge is worth paying?
Put the dollar figure next to what it solves. A $170 finance charge to keep a car on the road for work is a straightforward trade. The same charge for something that could wait a month usually is not.
Where can I see the cost for my amount?
Our loan amounts page lists the monthly payment for every amount and term we offer, and the calculator on the home page shows the full payment schedule.
Keep reading
Related guides and the pages that carry the underlying numbers.
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