Good record keeping is the foundation of accurate CT600 filing. Get it right, and preparing your Corporation Tax return becomes straightforward. Get it wrong, and you'll spend hours hunting for missing information — or worse, face HMRC penalties for inadequate records.

Here's exactly what records you need to keep, how long to keep them, and how to organize everything so tax time isn't stressful.

Legal requirements for company records

HMRC and Companies House require companies to maintain adequate records to support their tax returns and accounts. This isn't optional — it's a legal obligation.

Minimum retention period: 6 years

You must keep business records for at least 6 years from the end of the accounting period they relate to.

Example timeline

Accounting period: 1 April 2025 to 31 March 2026
Keep records until: 31 March 2032

Penalties for inadequate records

£3,000 penalty for failing to keep adequate records
Additional penalties if inadequate records lead to incorrect returns
HMRC investigations are more likely if records are poor

Essential records for CT600 filing

1. Company formation documents

Certificate of incorporation
Memorandum and Articles of Association
Share certificates and allotment records
Director appointment forms (AP01)
Annual confirmations filed with Companies House

2. Bank records

All business bank statements for the accounting period
Paying-in books or deposit slips
Cheque book stubs
Online banking transaction records
Credit card statements (business cards)

3. Sales and income records

Sales invoices (copies of all invoices sent)
Cash sale receipts
Bank interest statements
Dividend vouchers (income from other companies)
Rental income records (if applicable)
Export documentation
Contract agreements for services

4. Purchase and expense records

Purchase invoices from suppliers
Receipts for cash purchases
Expense claim forms (director/employee expenses)
Petrol receipts and mileage logs
Utility bills (business premises)
Insurance policy documents and payment records
Professional fees invoices (legal, accounting, etc.)

5. Payroll records (if you have employees)

Employment contracts
Payroll records (gross pay, deductions, net pay)
P45/P46 forms
P11D forms (benefits in kind)
P60 forms
PAYE/NIC payment records to HMRC

6. Asset records

Purchase invoices for equipment, vehicles, property
Depreciation calculations
Disposal records (sale proceeds, disposal costs)
Insurance valuations

What each record should contain

Sales invoices

Invoice number and date
Customer name and address
Description of goods/services
Quantity and unit price
VAT amount (if VAT registered)
Payment terms

Purchase receipts/invoices

Supplier name and address
Date of purchase
Description of goods/services
Amount paid
VAT breakdown (if VAT registered)
Business purpose (if not obvious)

Bank records

All transactions clearly identifiable
Purpose of payments noted
Transfers between accounts explained
Director loan account movements tracked

Digital vs paper records

HMRC accepts records in any format, provided they're:

Complete and accurate
Easily accessible when needed
Backed up (for digital records)
Readable throughout the retention period

Digital record advantages

Space efficient — no physical storage needed
Searchable — find specific transactions quickly
Backup friendly — multiple copies easy to maintain
Integration — link directly to accounting software

Common record keeping mistakes

1. Missing bank interest

Even £5 of bank interest is taxable income. Keep all bank statements showing interest credited.

2. Personal vs business expenses

Mixed personal/business expenses must be split clearly. Keep notes explaining the business portion.

3. Cash transactions

Cash purchases without receipts are hard to prove. Always get receipts, or keep detailed cash books.

4. Estimated figures

Never guess at figures. If you can't find exact amounts, HMRC may reject estimated figures.

5. Incomplete VAT records

If VAT registered, every transaction needs proper VAT documentation.

What HMRC looks for in records

Completeness

All income recorded (no gaps in invoice sequences)
All expenses supported by receipts/invoices
Bank accounts reconciled to records

Accuracy

Figures add up correctly
VAT calculations accurate
No unexplained differences

Timeliness

Records updated promptly (not all at year-end)
Transactions recorded in correct accounting periods

Supporting evidence

Original receipts/invoices (copies acceptable if originals lost)
Clear explanation of business purpose
Evidence of payment (bank statements, etc.)

Organizing records for CT600 preparation

Monthly routine

Bank reconciliation — match statements to accounting records
File receipts in date/category order
Update expense categories for new types of spending
Chase missing invoices from suppliers

Year-end preparation

Final bank reconciliation for the accounting period
Gather all receipts/invoices for the year
Prepare trial balance showing all income and expenses
Calculate fixed asset additions and disposals
Reconcile director loan accounts

Special situations

Working from home

Keep records of:

Home office expenses (proportion of household bills)
Equipment purchased for business use
Business calls made from home phone

Company car

Maintain:

Purchase/lease agreements
Fuel receipts and mileage logs
Insurance and maintenance costs
Personal use calculations for benefit-in-kind

Business travel

Record:

Purpose of each trip
Accommodation receipts
Travel tickets/receipts
Meal receipts (if overnight travel)

Preparing for HMRC enquiries

Even with good records, HMRC may enquire into your return. Good record keeping makes enquiries:

Shorter — HMRC can verify figures quickly
Less stressful — you can answer questions confidently
Cheaper — fewer hours of professional help needed

HMRC powers

HMRC can:

Request any business records related to your tax affairs
Visit your premises to inspect records (with notice)
Issue penalties for failure to produce records

At Taxpipe, we help company directors identify exactly what information they need for their CT600. Our system guides you through gathering the right records and shows you how to organize them for easy filing.

The key is to set up good systems from the start, rather than trying to organize everything at year-end.

The bottom line

Good record keeping isn't exciting, but it's essential. Spend a few minutes each month organizing your records, and CT600 preparation becomes straightforward.

The alternative — scrambling to find missing receipts and bank statements at year-end — is stressful, time-consuming, and increases your risk of errors and penalties.

Set up your record keeping system now, stick to it consistently, and thank yourself at tax time.

Your future self (and your accountant, if you use one) will be grateful for the effort.

Got your records ready?

Once you've gathered your documents, filing your CT600 with Taxpipe takes about 15 minutes. Our wizard asks plain-English questions — you don't need to know which box is which.

File your CT600 now →