Opex vs capex: what's the difference?

Published Wednesday 17 June 2026

Table of contents

• What is opex (operating expenditure)?
• What is capex (capital expenditure)?
• Key differences between opex and capex
• How opex and capex are treated for tax and accounting
• How to calculate opex and capex
• When to choose opex vs capex
• Track your business spending with Xero
• FAQs on opex vs capex

Key takeaways

• Opex covers your day-to-day running costs like wages, rent and utilities, while capex refers to longer-term investments in assets like equipment, property or vehicles.
• For tax purposes, opex is usually deducted in full in the year you spend it, but capex is spread over several years through depreciation or claimed via the Annual Investment Allowance.
• Choosing between opex and capex affects your cash flow, tax position and financial statements, so it's worth understanding the trade-offs before committing to a large purchase or subscription.
• Cloud-based software and leasing arrangements have made it easier than ever for small businesses to shift spending from capex to opex, keeping more cash available month to month.

What is opex (operating expenditure)?

Operating expenditure (opex) is the money you spend to keep your business running on a daily basis. These are the recurring costs that don't result in a long-term asset on your balance sheet.

Common examples of opex include wages and salaries, office rent, utility bills, insurance premiums, marketing spend and office supplies. If you're paying for something that gets used up within the financial year, it's almost certainly opex.

Opex shows up on your profit and loss statement (also called an income statement) as an expense in the period you incur it. It also flows through your cash flow statement, giving you a clear picture of how much cash leaves the business each month.

It's worth noting that cost of goods sold (COGS) is technically a separate line item from operating expenses on your profit and loss statement. COGS covers the direct costs of producing what you sell, while opex covers the broader costs of running the business.

What is capex (capital expenditure)?

Capital expenditure (capex) is the money you spend on assets that will benefit your business over a longer period, typically more than 1 year. These purchases appear on your balance sheet as fixed assets rather than being expensed immediately.

Typical capex includes machinery, commercial property, company vehicles, computer hardware and major technology systems. If an item has a useful life beyond the current financial year and adds lasting value, it's likely capex.

There are 2 broad types of capex to be aware of. Maintenance capex covers spending to keep existing assets in working order, like replacing a worn-out component in a machine. Growth capex covers new investments that expand your capacity, such as buying additional equipment or fitting out a second premises.

Because capex assets deliver value over multiple years, you don't deduct the full cost in the year of purchase. Instead, the cost is spread across the asset's useful life through depreciation. Each year, a portion of the asset's value moves from the balance sheet to the profit and loss statement as a depreciation expense.

Key differences between opex and capex

While both opex and capex represent money leaving your business, they're treated very differently in your accounts and tax returns. Here's how they compare across 4 key areas.

Time horizon

Opex covers short-term, recurring costs that are consumed within the financial year. Capex involves longer-term investments in assets you'll use for several years. This distinction drives how each type of spending is recorded and reported.

Impact on profitability

Opex reduces your reported profit in the period you spend it, since the full amount appears on your profit and loss statement straight away. Capex, on the other hand, only reduces profit gradually through annual depreciation charges. A large capital purchase won't wipe out your profit in a single year.

Flexibility and timing

Operating expenses tend to be more flexible. You can often scale them up or down relatively quickly, for example by adjusting your marketing budget or renegotiating a service contract. Capital expenditure usually involves a larger upfront commitment that locks in spending for years, making it harder to reverse if circumstances change.

Predictability

Many operating expenses are predictable month to month: rent, salaries, subscriptions and utility bills follow a regular pattern. Capital expenditure is often irregular and harder to forecast, since it depends on when assets need replacing or when growth opportunities arise.

How opex and capex are treated for tax and accounting

The way you account for opex and capex affects both your financial statements and your tax position, so it's useful to understand the basics.

Operating expenses are recorded on your profit and loss statement in the period they occur. You can typically deduct the full amount from your taxable profit in the same year, which reduces your tax bill straight away.

Capital expenditure works differently. The asset goes onto your balance sheet at its purchase price, and its cost is then gradually expensed through depreciation over the asset's useful life. For tax purposes, His Majesty's Revenue and Customs (HMRC) doesn't use accounting depreciation. Instead, you claim capital allowances to deduct the cost of qualifying assets.

The Annual Investment Allowance (AIA) lets most UK businesses deduct the full cost of qualifying plant and machinery in the year of purchase, up to the current threshold of £1,000,000. This can significantly accelerate the tax relief you receive on capital spending. It's always worth checking the latest AIA limits on HMRC's website, as thresholds can change.

Getting the classification right matters, especially with Making Tax Digital (MTD) requiring digital record-keeping for VAT and, from April 2026, for Income Tax. If you treat a capital purchase as an operating expense (or vice versa), your financial statements won't give an accurate picture of the business, and you could end up paying the wrong amount of tax.

How to calculate opex and capex

Calculating your operating and capital expenditure doesn't require complicated maths, but it helps to know the standard formulas.

To calculate opex, add up all your operating costs for the period. This includes rent, wages, utilities, insurance, marketing and any other day-to-day business expenses. The formula is straightforward:

OpEx = total operating costs for the period

You'll find this figure on your profit and loss statement, either as a single total or broken down by category.

Calculating capex from your financial statements uses this formula:

CapEx = PP&E (current period) − PP&E (prior period) + depreciation

PP&E stands for property, plant and equipment, which you'll find on your balance sheet. By taking the change in PP&E and adding back the depreciation charged during the period, you arrive at the total amount spent on new capital assets.

When to choose opex vs capex

The choice between opex and capex isn't always clear-cut, and the right answer depends on your business's cash flow, growth plans and risk appetite.

Opex gives you flexibility. Monthly or annual subscriptions, leasing arrangements and pay-as-you-go services keep your cash flow steady and let you adjust spending quickly if conditions change. This is why many small businesses now choose cloud-based software (an operating expense) over traditional on-premises systems (a capital expense).

Capex makes sense when you need an asset that will deliver value for years and you have the cash (or financing) to cover the upfront cost. Owning equipment outright can be cheaper in the long run, and you may benefit from capital allowances that reduce your tax bill.

In practice, most small businesses use a mix of both. You might lease your office space (opex) but purchase specialist tools or machinery (capex). The key is to weigh up the total cost of ownership, the impact on your cash flow and how each option affects your tax position before making a commitment.

Track your business spending with Xero

Whether you're managing day-to-day operating costs or tracking the depreciation on a major purchase, having clear visibility over your spending makes it easier to plan ahead and stay on top of your tax obligations. Xero helps you track business expenses and keep accurate records. Xero Accounting Software lets you categorise expenses, monitor cash flow in real time and pull the reports you need at tax time. Get one month free.

FAQs on opex vs capex

Here are answers to some frequently asked questions about opex vs capex.

Is software capex or opex?

It depends on how you acquire it. Cloud-based software paid for through a monthly or annual subscription is treated as opex. Software you purchase outright and install on your own hardware is typically classified as capex and depreciated over its useful life.

Can you convert capex to opex?

Yes, in many cases. Leasing an asset instead of buying it, or switching from on-premises software to a cloud subscription, effectively converts what would have been capex into opex. This can free up cash and simplify your accounting.

Which is better for a small business, capex or opex?

Neither is inherently better. Opex offers flexibility and preserves cash flow, while capex can be more cost-effective over time and may qualify for tax relief through capital allowances. The best approach depends on your financial situation, growth plans and how quickly you need to adapt.

How are capex and opex reported on financial statements?

Opex appears on your profit and loss statement as an expense in the period it's incurred. Capex is recorded on the balance sheet as a fixed asset and then gradually expensed through depreciation over the asset's useful life.