Connect to HMRC
Link your HMRC account to Calceum using Government Gateway.
User Guides
User Guides
Section titled “User Guides”Practical guides to help you get the most out of Calceum.
Getting started
Section titled “Getting started”Your first submission
Walk through making your first quarterly submission.
Connect to HMRC
Section titled “Connect to HMRC”Before you can submit to HMRC, you need to authorise Calceum to act on your behalf.
- Sign in to Calceum and go to Settings 2. Click “Connect to HMRC” - you’ll be redirected to HMRC’s Government Gateway 3. Sign in with your Government Gateway credentials 4. Grant permission for Calceum to submit on your behalf 5. Return to Calceum - your account is now connected
What permissions does Calceum need?
Section titled “What permissions does Calceum need?”When you connect, you’re granting Calceum permission to:
- View your business details
- View your tax obligations and deadlines
- Submit quarterly updates on your behalf
- Submit your final declaration
You can revoke this access at any time through your HMRC online account.
Your first submission
Section titled “Your first submission”Once you’re connected to HMRC, here’s how to make your first quarterly submission.
- Download the spreadsheet template from your Calceum dashboard 2. Enter your transactions - income and expenses for the period 3. Upload your completed spreadsheet to Calceum 4. Review the summary - check the totals look correct 5. Click Submit - Calceum sends your data to HMRC 6. Save your confirmation - you’ll receive a receipt from HMRC
Recording transactions
Section titled “Recording transactions”What to record
Section titled “What to record”For each transaction, you need:
| Field | Description | Example |
|---|---|---|
| Date | When the transaction occurred | 15/07/2026 |
| Description | Brief description | Client invoice - ABC Ltd |
| Category | Income or expense type | Turnover / Office costs |
| Amount | Gross amount (before VAT) | £1,200.00 |
| VAT | VAT amount if applicable | £240.00 |
Income categories
Section titled “Income categories”- Turnover - Your main business income
- Other income - Secondary income sources
Expense categories
Section titled “Expense categories”Common expense categories include:
- Cost of goods sold - Stock, materials, direct costs
- Office costs - Stationery, software, phone bills
- Travel - Business mileage, public transport
- Professional fees - Accountant, legal costs
- Advertising - Marketing and promotion
- Premises - Rent, utilities, insurance
- Repairs - Maintenance and repairs
Quarterly deadlines
Section titled “Quarterly deadlines”MTD requires four submissions per tax year. Here are the deadlines:
| Quarter | Period | Deadline |
|---|---|---|
| Q1 | 6 April - 5 July | 7 August |
| Q2 | 6 April - 5 October | 7 November |
| Q3 | 6 April - 5 January | 7 February |
| Q4 | 6 April - 5 April | 7 May |
Year-end process
Section titled “Year-end process”After your fourth quarterly submission, you’ll need to:
- Review your totals - Check everything is accurate for the year 2. Add adjustments - Capital allowances, private use adjustments, etc. 3. Submit your final declaration - Confirm your figures to HMRC
The final declaration deadline is 31 January following the end of the tax year - the same as the current Self Assessment deadline.
Need help?
Section titled “Need help?”- Contact support - We’re here to help
- FAQ - Common questions answered
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