A business overdraft is a credit facility on your business current account that lets you dip beyond your available balance, up to a limit agreed with your bank. You only pay interest on what you borrow, and once you repay it, the funds are available to use again.

Most major UK banks offer overdraft limits from £500 to £50,000, although the amount you’re offered depends on your trading history and financial position. Rates vary too, and they’re often higher than most business loans, especially if you use the overdraft regularly rather than occasionally.

The biggest selling points are speed and flexibility. Once the facility is in place, you can draw on it as needed without making a fresh application. The trade-off is cost and control, because your bank can review, reduce, or withdraw the facility with limited notice.

In this guide, we break down the advantages and disadvantages of a business overdraft, how costs are calculated, and when another type of finance may be a better fit.

What is a business overdraft?

A business overdraft is a borrowing facility attached to your business current account. It lets you spend more than your available balance, up to a limit set by your bank. You can use it when you need to, repay it when funds come in, and use it again.

That flexibility is what makes it different from a business loan. With a loan, you receive a lump sum and repay it over a fixed term. With an overdraft, the balance can go up and down, and the full limit becomes available again once you clear what you owe.

There are two types to be aware of:

• Arranged overdraft: agreed with your bank in advance, with a set limit, interest rate, and review period.

• Unarranged overdraft: when your account goes below zero without an agreement in place, or you go beyond your agreed limit. Fees and interest are usually much higher, and most banks will treat it as a breach of your account terms.

An overdraft is tied to your current account. That means you can only have one with your existing bank. If you want a better rate elsewhere, you’d usually need to move your whole business banking relationship.

Advantages of a business overdraft

The main advantages of a business overdraft are flexibility, speed, and the fact it can be cost effective when it’s used for short, occasional gaps in cash flow.

You only pay interest on what you use

With a business overdraft, you’re charged interest on the amount you actually borrow, not the full limit. If your limit is £20,000 but you only use £3,000 for a week, you’ll pay interest on £3,000 for seven days. The unused portion costs you nothing, which can make an overdraft cheaper than a loan when you need a small amount for a short time.

It’s quick to access once set up

Once your bank has approved the facility, the funds are there in your current account. You don’t need to make a new application each time you want to use it. If a supplier invoice lands on Tuesday and a customer payment is due on Friday, an overdraft can cover the gap without delays.

There’s no fixed repayment schedule

Unlike a business loan, an overdraft doesn’t come with set monthly repayments. You can clear the balance when cash comes in, or pay it down gradually. In many cases, banks expect the account to return to credit from time to time, and they may review the facility if it stays overdrawn for long periods.

You can reuse it once you’ve paid it back

As soon as you reduce or clear the balance, your available limit increases again. If your cash flow is seasonal, or your income is uneven month to month, that ongoing access can be more practical than applying for a new loan every time a gap appears.

It stops you missing payments when cash is tight

Missing supplier payments or failing direct debits can strain relationships and create extra costs, such as charges or service interruptions. An overdraft can give you a buffer so you can keep key outgoings on track while you’re waiting for money owed to you.

Disadvantages of a business overdraft

Used badly, a business overdraft can become expensive, and your bank can change the terms with limited notice.

The main disadvantages of a business overdraft are cost, control, and limited choice. Rates are often higher than most business loans, your bank can reduce or recall the facility at short notice, and you’re tied to whichever bank holds your current account.

Interest rates are higher than most business loans

Overdraft pricing varies by bank and by the strength of your business, but arranged overdrafts are often priced higher than fixed term business loans for the same borrowing. For short, occasional dips that can be manageable. If you’re consistently overdrawn, the cost builds quickly, and a term loan or revolving credit facility is usually cheaper.

The bank controls the facility, not you

A business overdraft is typically repayable on demand. That means your bank can ask for repayment, or reduce your limit, with limited notice. In practice, this is more likely if your financial position changes, but overdrafts are reviewed periodically, often at least once a year. If turnover has dropped, the account has stayed close to the limit for months, or you’ve missed payments elsewhere, don’t assume your current terms will stay the same.

You can only get one from your existing bank

A business overdraft is tied to your current account, so you can’t shop around in the same way you can with a loan or invoice finance. If your bank’s pricing isn’t competitive, switching provider usually means moving your whole business banking relationship, which can be disruptive.

Rates are variable, so costs are hard to predict

Overdraft pricing is usually variable. Some banks link it to a reference rate, and others set a variable EAR. Either way, when rates rise, your borrowing costs can rise too, which makes budgeting harder, especially if you’re using the facility regularly.

It’s easy to become dependent on it

An overdraft is designed as a short term buffer, not a permanent source of working capital. Because it’s always there and easy to draw on, it can become a habit. If you’re overdrawn more often than not, the underlying issue is usually wider cash flow rather than a one off timing gap, and an overdraft can end up masking that.

How much does a business overdraft cost?

The cost depends on how much you borrow and how long you stay overdrawn. Interest is calculated daily on the amount you’re overdrawn by, then applied to your account monthly.

Most UK banks charge between 10% and 19% EAR on arranged business overdrafts, depending on the size of the facility and your credit profile. On top of interest, you’ll usually pay an arrangement fee when the overdraft is set up, a renewal fee when it’s reviewed (often every 12 months), and penalty charges if you go beyond your agreed limit.

Arrangement fees vary. Some banks charge a flat fee from around £25, while others charge a percentage of the limit, usually between 1% and 2%. Renewal fees tend to be lower, but they’re still worth factoring in if you plan to keep the facility running year on year.

• For example: Say your bank has approved a £15,000 business overdraft at 12% EAR. You need to cover an £8,000 cash flow gap for 14 days while you wait for a customer payment to clear. The daily interest rate is roughly 0.033% (12% divided by 365). On £8,000 over 14 days, that’s around £37 in interest.

For a fortnight of breathing room, many businesses would consider that reasonable. But if that same £8,000 stayed overdrawn for three months, you’d be looking at closer to £240, and that’s before fees. The longer you stay overdrawn, the less an overdraft makes sense compared to a fixed term loan or revolving credit facility.

If you go beyond your agreed limit without arrangement, costs can jump sharply. Unauthorised overdraft rates at major UK banks can be as high as 29.5%, and most will charge a penalty fee on top.

When to use a business overdraft (and when not to)

A business overdraft is most useful when cash flow is out of sync for a short period. You’re waiting on money to land, but wages, VAT, or a supplier invoice has to be paid now.

Because it sits on your account, it’s easy to start treating it like part of your balance. If you’re dipping into it month after month, it stops being a safety net and starts getting expensive.

If you’re deciding between a business overdraft and a business loan, think about how long you’ll carry the borrowing. Overdrafts are made for short gaps and smaller amounts you’ll clear quickly. If you’ll be carrying the balance for months, a loan is often cheaper and far easier to budget for.

If late-paying customers are the reason you’re short, invoice finance can make more sense because it brings the cash forward. If you’re using borrowing for a one-off purchase, a fixed-term business loan is usually cheaper and easier to plan around.