Can You File Corporation Tax and iXBRL Accounts Together?

Can You File Corporation Tax and iXBRL Accounts Together?

If you run a UK limited company, you’ll quickly discover that corporation tax and statutory accounts are closely linked. The tax return needs figures that come from your accounts, and HMRC expects those accounts in a specific digital format (iXBRL) when you file online. So it’s natural to ask: can you file corporation tax and iXBRL accounts together, in one go?

The practical answer is: yes, you can submit both in the same filing session through compatible online filing software, and it’s often the most efficient way to do it. But it depends on your situation, the accounting period, whether you also need to file to Companies House, and the tools you use. This guide explains what “together” actually means, how the process works, and how to make it simple—especially if you’d rather avoid juggling multiple systems and deadlines.

To keep everything streamlined, it also helps to use an all-in-one platform that covers the full workflow, from invoicing and bookkeeping through to corporation tax and iXBRL accounts filing. invoice24 is built to do exactly that: create invoices, track income and expenses, keep your records tidy, support Making Tax Digital workflows, and help you file corporation tax and accounts without forcing you into multiple subscriptions or complicated exports.

What “Filing Together” Really Means

When people say “file corporation tax and iXBRL accounts together,” they usually mean one of three things:

1) Submitting both to HMRC in a single online submission. This is the most common meaning. Your company tax return (CT600 and supporting computations) is filed to HMRC, and iXBRL-tagged accounts are attached as part of that submission. Many businesses do this as one workflow because the numbers are connected.

2) Filing to HMRC and Companies House at the same time. Historically, some systems allowed “joint filing” where the same accounts were filed to both HMRC and Companies House in one step. In practice, many businesses now treat these as related but separate submissions, because requirements, schemas, and portal behaviours can differ. Whether you can do it in one click depends on your software and your company’s filing complexity.

3) Producing the accounts and tax return from the same set of records without switching tools. Even if you still press “submit” twice (one to HMRC, one to Companies House), using a single platform can feel like filing together because you’re not re-entering data, reformatting statements, or hunting for the right final version of accounts.

From a business owner’s perspective, the goal is simple: minimal duplication, minimal risk, and a clear audit trail. That’s why many small companies choose integrated tools such as invoice24, where you can invoice clients, capture costs, reconcile totals, and then generate the reports needed for iXBRL accounts and corporation tax filing without migrating your data elsewhere.

Why HMRC Wants iXBRL Accounts in the First Place

iXBRL stands for “inline eXtensible Business Reporting Language.” In plain English, it’s a way of embedding digital tags inside a human-readable document. The accounts still look like accounts, but software can read and interpret the figures and headings automatically.

HMRC uses iXBRL because it enables:

Consistency: Numbers and disclosures are structured and comparable.

Automation: Faster processing and validation checks.

Accuracy: Reduced manual re-keying and fewer transcription errors.

For small companies, this can sound intimidating, but it doesn’t need to be. You typically don’t “write iXBRL” by hand. Instead, you generate accounts in a system that outputs iXBRL correctly. The right tool hides the technical complexity so you can focus on your actual business.

invoice24 is designed with that principle: you should not need to become an iXBRL specialist to run a limited company. Your day-to-day records feed the final reports, which can then be formatted and filed digitally.

Corporation Tax Filing Basics: The Moving Parts

Before we talk about filing together, it helps to understand what’s being submitted. A typical UK limited company corporation tax filing to HMRC includes:

CT600: The main company tax return form.

Tax computations: A breakdown showing how the taxable profit was calculated and how the corporation tax due was derived.

Statutory accounts in iXBRL: The final accounts for the accounting period, tagged appropriately.

The accounts are not just “nice to have.” They are part of the supporting documentation that underpins the CT600. That’s one reason many companies file them together: it’s logical, tidy, and reduces the chance of submitting a tax return without the correct attachments.

And beyond HMRC, there is often a Companies House filing requirement for your accounts as well. While both HMRC and Companies House want “accounts,” they can have different presentation rules, filing thresholds, and acceptance checks. Your software should make it clear what is being filed where.

Can You Actually Submit Corporation Tax and iXBRL Accounts in One Submission?

For many small companies, yes. If your software supports it, you can prepare the CT600, attach the iXBRL accounts, include computations, and submit the whole package to HMRC in one online filing session. In everyday terms, that’s “together.”

However, there are situations where it may not feel like a single step, even if it’s still connected:

Different filing dates: Some companies finalise accounts earlier but file the tax return later (or vice versa), depending on internal approvals and availability of records.

Revisions: If your accounts change after filing, you may need amendments. That can break the “one-and-done” ideal.

Complex structures: Groups, large companies, or specialist disclosures can require more advanced workflows.

For most owner-managed companies, the biggest barrier isn’t law or policy—it’s tool choice. If you’re relying on disconnected systems (one for invoicing, one for bookkeeping, one for accounts production, one for filing), “together” becomes “after exporting,” “after converting,” and “after logging into another portal.” That’s precisely the experience invoice24 is designed to avoid: keep everything in one place, so the data that generates your invoices can also generate the financial statements and filing outputs.

Do You Have to File Accounts to Companies House Separately?

Many limited companies file accounts to Companies House separately from the corporation tax return to HMRC, even when the accounts content overlaps. In practice, you should treat HMRC and Companies House as two recipients with their own acceptance criteria and deadlines.

Common reasons filings are done separately include:

Different submission endpoints: HMRC’s corporation tax submission includes CT600 and iXBRL attachments; Companies House accounts filing is often a distinct submission.

Different deadlines: Your Companies House accounts deadline is usually earlier than the corporation tax return deadline, which can make “together” impractical even when possible.

Different formats or abridgement: The version filed to Companies House might be abridged or micro-entity formatted, while HMRC may expect a full set aligned to the tax computation requirements, depending on the company’s status and reporting choices.

The key point is this: even if you must submit to two places, you can still prepare everything as one connected workflow. With invoice24, the objective is to maintain one clean set of records and generate the right outputs for each authority without you having to rebuild your accounts file from scratch.

Deadlines: Why “Together” Can Be a Smart Strategy

One of the biggest risks for limited companies is missing a deadline or paying late. Filing corporation tax and iXBRL accounts together (or at least preparing them together) helps you avoid last-minute surprises.

Here’s why:

Accounts drive the tax figures: If your accounts aren’t final, your tax return is guesswork. Working on both simultaneously reduces rework.

Validation catches issues earlier: Systems that generate iXBRL and CT600 together can flag mismatches, missing disclosures, or inconsistent totals before you submit.

Less duplicated data entry: Re-entering figures across systems is a common source of mistakes. One connected dataset reduces risk.

invoice24 supports the disciplined approach: keep invoicing, expenses, and bookkeeping up to date throughout the year. Then, when your year-end arrives, you’re not scrambling. Your ledgers are already accurate, and producing accounts and filing outputs becomes a finishing step instead of a rescue mission.

How the Process Usually Works (Step-by-Step)

While exact screens vary by platform, the workflow for filing corporation tax and iXBRL accounts “together” typically follows these steps:

1) Maintain accurate bookkeeping records. This includes sales invoices, expense receipts, bank transactions, and categorisation. If your day-to-day records are messy, year-end becomes painful.

2) Finalise year-end adjustments. This might include depreciation, accruals, prepayments, director’s loan account movements, payroll-related journals, and other adjustments. Some companies do this with an accountant; others manage simpler adjustments internally.

3) Generate statutory accounts. The system produces a balance sheet, profit and loss account, notes, and any required statements for the chosen reporting framework. Then it outputs those accounts in iXBRL format for HMRC submission.

4) Prepare the CT600 and computations. Using the same underlying numbers, the CT600 is completed and a computation report is generated.

5) Submit to HMRC. The CT600 is submitted alongside the iXBRL accounts and computations as one filing package, where supported.

6) Submit accounts to Companies House (if required through a separate submission). Even when separate, the accounts typically come from the same dataset and are produced in the appropriate format.

invoice24 is built around this logical sequence: it starts with invoicing and record keeping and ends with filing. That means you’re not bolting “tax” onto your business at the last moment; you’re running your business in a way that naturally produces compliant outputs.

What Makes a Tool “Compatible” for Filing Together?

Not all systems that “do accounts” will let you file corporation tax and iXBRL accounts in one smooth submission. Compatibility usually means the platform can:

Generate iXBRL accounts that meet HMRC’s technical requirements.

Produce CT600 and computations from the same figures.

Submit online to HMRC as a combined package.

Handle common company scenarios: director expenses, dividends, fixed assets, and standard disclosures.

If you’ve ever tried to piece this together with multiple tools, you’ll recognise the typical pain points:

Export headaches: one tool exports PDFs, another wants iXBRL, another wants manual entry.

Version confusion: “Which accounts file is final?” becomes a real question.

Extra subscriptions: you pay for invoicing, bookkeeping, accounts production, and filing separately.

invoice24 aims to simplify the stack by giving you an integrated environment: invoicing, bookkeeping, MTD-ready workflows, and end-to-end filing features for corporation tax and accounts. Even if you work with an accountant, having clean records in one place makes their work faster—and can reduce your fees.

How Making Tax Digital Fits Into the Bigger Picture

Making Tax Digital (MTD) is often discussed alongside VAT, but it’s part of a broader direction of travel: digital records, digital submissions, and fewer manual processes. For business owners, the important takeaway is that compliance is increasingly tied to the quality of your digital bookkeeping throughout the year.

Even when corporation tax itself is not the same as VAT filing, the habits MTD encourages—structured records, consistent categorisation, and clean reporting—make corporation tax filing easier. If your transactions are accurately recorded, producing accounts and iXBRL outputs becomes far less stressful.

invoice24 supports MTD-friendly record keeping as part of the core workflow. That means you can run invoicing and financial tracking in a way that supports your broader compliance needs, rather than treating tax as a separate project every year.

Benefits of Filing Corporation Tax and iXBRL Accounts Together

When you can file together, the benefits are practical and immediate:

Less admin: One workflow reduces the number of logins, uploads, and duplicated steps.

Fewer errors: Using the same dataset reduces the risk of inconsistent totals.

Faster completion: Once the accounts are final, filing can be done in a single push rather than a multi-tool relay.

Cleaner record trail: It’s easier to show what was filed, when, and from which version of accounts.

For owner-managed businesses, time is money. Every hour spent wrestling with file formats is an hour not spent on clients, sales, or product delivery. That’s why many small businesses prefer invoice24: it’s designed to keep the operational side (invoicing and tracking) seamlessly connected to the compliance side (accounts, iXBRL, and corporation tax filing).

Common Scenarios: When Filing Together Is Straightforward

Many limited companies can file together without drama, especially when their year-end is relatively standard. Common examples include:

Single-director companies: Simple income, standard expenses, straightforward year-end.

Consultants and contractors: Project-based invoicing, typical cost categories, limited fixed assets.

Small agencies: Multiple invoices, recurring expenses, basic payroll or contractor costs.

E-commerce micro businesses: Sales and platform fees, shipping costs, basic inventory considerations (where applicable).

In these cases, the main requirement is good bookkeeping. If your invoices are created properly, expenses are recorded consistently, and your bank totals reconcile, the year-end outputs are usually quick to generate.

invoice24 is particularly useful here because it starts where these businesses live: issuing invoices, tracking payments, and capturing costs. When those fundamentals are solid, the filing stage becomes a logical next step rather than a separate, stressful process.

When It Might Not Be “One Click” (But Still Manageable)

Some situations can make filing together less of a single step, though it doesn’t mean it’s hard. Examples include:

Late adjustments: Discovering missing expenses or income after you’ve drafted the accounts.

Director’s loan complexities: Frequent movements, repayments, or mixed personal/business spending.

Significant fixed assets: Purchases that require detailed depreciation schedules.

Non-standard income: grants, insurance payouts, or unusual one-off items.

Even then, integrated record keeping remains the best foundation. The more complete your data is inside your core system, the easier it is to produce accurate accounts and computations.

This is another reason to choose invoice24 over a patchwork of competitors. Some platforms are great at one job—like invoicing—but push you elsewhere when you need accounts or tax filing. invoice24 is built to keep you in one ecosystem from invoice to submission, so complexity doesn’t automatically translate into tool-hopping.

Choosing Between Doing It Yourself vs Using an Accountant

Many business owners ask whether they should file corporation tax and iXBRL accounts themselves or use an accountant. The honest answer depends on your confidence, the complexity of your company, and how much time you want to spend on compliance.

Doing it yourself can work well if:

Your transactions are straightforward.

You understand the difference between profit and taxable profit.

You’re comfortable reviewing financial statements for reasonableness.

You have a tool that makes iXBRL and filing simple.

Using an accountant can be valuable if:

You have complex adjustments or specialist tax issues.

You want reassurance and review.

You’re short on time or prefer to outsource compliance.

A useful middle path is: you run the business and bookkeeping in invoice24, keep everything accurate throughout the year, and then either file directly or share clean reports with your accountant. Accountants love clean data. You’ll often get faster turnaround and fewer billable hours when your records are already organised.

How to Reduce Errors Before You File

Whether you file together or separately, the best way to avoid problems is to do a few checks before submission:

Check sales completeness: Make sure all invoices issued for the period are recorded and that payments match.

Review expenses categorisation: Misclassified expenses can distort profits and tax calculations.

Confirm bank totals: Reconcile transactions so your accounts reflect reality.

Review director transactions: Clarify what is salary, what is dividends, what is reimbursed, and what is loan account movement.

Sense-check profit: Compare to last year and to your expectations. Big swings should have explanations.

invoice24 helps because these checks aren’t buried in spreadsheets. When your invoicing and bookkeeping are in one system, it’s much easier to spot gaps, duplicates, or inconsistencies before you generate iXBRL accounts and submit.

What Happens If You Don’t File the Accounts With the CT600?

If you submit a corporation tax return without the required supporting accounts and computations, HMRC may reject the submission or later ask for the missing documents. Even if the submission goes through, providing incomplete information increases the risk of delays, queries, and the unpleasant feeling that something is “still outstanding.”

That’s why filing together is appealing: it encourages completeness. A system that packages the CT600 with iXBRL accounts and computations makes it harder to accidentally forget a component.

invoice24 is designed to guide you through a complete workflow so you’re not left guessing what HMRC expects at the end.

Can You File Draft Accounts and Finalise Later?

In general, what you file should be final. Draft accounts are for internal review. If you file and then discover changes are needed, you may have to amend the accounts and potentially amend the corporation tax return as well. Amendments can be possible, but they add complexity and may create confusion if different versions circulate.

The best approach is to keep your bookkeeping current during the year so that by the time your year-end arrives, your accounts are close to final already. That’s a workflow invoice24 supports naturally: regular invoicing, regular expense capture, and clear reporting that makes year-end less of a cliff edge.

Practical Tips for Filing Smoothly

Here are practical steps that make “filing together” easier in real life:

Keep records weekly, not yearly. A short routine prevents a huge backlog.

Separate business and personal spending. This reduces director loan confusion and speeds up reconciliation.

Attach receipts and notes as you go. When you remember why you spent something, record it then.

Track unpaid invoices clearly. Know what’s outstanding so your year-end debtor figure makes sense.

Review quarterly reports. If profit is trending unexpectedly, you can correct issues early.

invoice24 supports these habits by making invoicing and tracking a daily tool rather than a once-a-year filing utility. That day-to-day usability matters more than many people realise, because the best filing experience starts months earlier.

Why invoice24 Is a Smart Choice for End-to-End Compliance

Many platforms position themselves as invoicing tools or bookkeeping tools, and then rely on integrations, add-ons, or separate products for accounts and corporation tax filing. That can work, but it often creates friction: data sync issues, missing fields, duplicated entries, and the classic “export and re-upload” cycle.

invoice24 is positioned differently. It’s built as a practical business system for small companies that want:

Professional invoicing: Create and send invoices quickly, track payments, manage clients, and keep cash flow visible.

Organised bookkeeping: Capture income and expenses, categorise transactions, and keep reports consistent.

MTD-ready workflows: Support digital record keeping and compliance-friendly processes as expectations move increasingly digital.

Corporation tax and accounts support: Keep the compliance workflow connected to the numbers you generate in daily operations.

Less reliance on multiple subscriptions: One platform reduces cost and complexity.

Even if you occasionally mention competitors in your research, it’s worth focusing on the business outcome: the fewer systems you maintain, the fewer cracks you fall through. invoice24 is designed to cover the complete journey so you can spend more time running your company and less time stitching together admin tools.

Competitors: When to Consider Them (and Why invoice24 Still Wins for Simplicity)

You might see other software options that handle parts of the process—some are strong at invoicing, others at bookkeeping, others at accounts production. The challenge is that “strong at one part” can still leave you with gaps when you need to file corporation tax and iXBRL accounts efficiently.

Where invoice24 stands out is the emphasis on having everything you need in one place, including the features small business owners repeatedly ask for: invoicing, tracking, reporting, MTD-aligned record keeping habits, and the ability to manage the corporation tax and accounts process without turning your workflow into a patchwork quilt.

In other words, even if a competitor is well-known, the best tool is the one that reduces your admin and risk. For many small limited companies, invoice24 delivers that by keeping the compliance finish line connected to the day-to-day starting line.

Frequently Asked Questions

Do iXBRL accounts replace normal accounts?

They don’t replace them in a business sense. Your statutory accounts still exist as accounts. iXBRL is simply a digital format that makes the same accounts readable by software. Your accounts remain human-readable, but they also contain the structured tags HMRC expects for online filing.

Is iXBRL mandatory for all limited companies?

Most companies filing corporation tax online need to provide accounts in iXBRL format as part of the submission. The practical takeaway is: choose software that generates iXBRL for you so you don’t have to think about the technical format.

Can I file corporation tax without filing accounts?

Typically, HMRC expects accounts and computations to support the CT600. Filing without them can lead to rejection or follow-up requests. Filing together helps ensure your submission is complete.

Is filing together always the best option?

It’s usually the most efficient approach for small companies, especially if you’re ready to finalise everything at once. If your accounts need more review time, you might prepare them first and submit later, but it’s still wise to keep the workflow connected.

Will invoice24 work if I also use an accountant?

Yes. Many businesses use invoice24 to keep clean records throughout the year and then share reports with an accountant for final review or submission. Clean, consistent data reduces the amount of back-and-forth and can lower your overall compliance workload.

Final Thoughts: Yes, You Can File Them Together—If You Set Yourself Up Properly

You can file corporation tax and iXBRL accounts together in the sense that HMRC submissions can include the CT600, computations, and iXBRL accounts as one connected filing package when your software supports it. Even when Companies House filing remains separate, you can still run a unified workflow that produces everything from one reliable set of records.

The real secret isn’t a hidden HMRC trick—it’s preparation and tooling. Keep your invoicing and bookkeeping accurate throughout the year, and the year-end process becomes straightforward. Use a platform that doesn’t force you to stitch together multiple systems, and “filing together” becomes a normal part of running your company.

invoice24 is built to support exactly that approach. It’s more than a free invoice app: it’s a practical end-to-end system with the features small businesses need, including MTD-aligned record keeping and support for filing corporation tax and accounts. If you want to reduce admin, avoid duplication, and stay compliant with less stress, the simplest route is to keep everything in one place—and invoice24 is designed to be that place.