HMRC recognised agent software
How to File
VAT Returns
as an Agent
A complete step-by-step guide for UK accountants, bookkeepers, and tax agents to file MTD VAT returns on behalf of clients using HMRC-recognised software.
What Is MTD VAT Filing for Agents?
Making Tax Digital (MTD) for VAT requires all VAT-registered businesses to keep digital records and submit VAT returns using HMRC-recognised software. As an accountant, bookkeeper, or professional tax agent, you can file VAT returns on behalf of your clients through your HMRC Agent Services Account (ASA).
11taxassist is HMRC-recognised MTD software designed specifically for agents who need to manage multiple clients, upload VAT data via Excel, and submit returns directly to HMRC through the official MTD API.
What You Need Before You Start
Government Gateway
Agent Government Gateway user ID and password
Agent Services Account
HMRC ASA set up and active for MTD services
Agent Reference Number
Your unique ARN from HMRC agent registration
Client Authorisation
Digital authorisation from each client via HMRC
Agent VAT Filing Process in 8 Steps
Follow these 8 steps to file MTD VAT returns on behalf of your clients. From HMRC agent registration to digital submission — everything you need in one guide.
Register as an HMRC Agent
Before filing VAT returns for clients, you must be a registered HMRC agent. You will need:
- Government Gateway Agent Account
- Unique Taxpayer Reference (UTR)
- Business identity details
- Agent contact information
Sign Up on 11taxassist
Create your free account at 11taxassist and select Agent as your user type:
- Enter your Agent Reference Number (ARN)
- Connect to your HMRC Agent Services Account
- Add your agent business details
Get Client Authorisation
HMRC requires digital authorisation for each client before you can file on their behalf:
- Log in to your Agent Services Account
- Select “Ask a client to authorise you”
- Enter the client’s VAT registration number
- HMRC sends a digital authorisation link
- Client approves the request online
Add Client & Select VAT Period
Once authorised, add the client’s details and choose their open VAT obligation period:
- Client’s VAT registration number
- Business name & details
- Open quarterly VAT period (fetched from HMRC)
Download VAT Templates
Download HMRC-aligned Excel templates for each client:
- VAT100 Template — for VAT return boxes (1–9)
- Bookkeeping Template — for sales & purchases
Enter & Upload Client Data
Fill in your client’s sales, purchases, output VAT, and input VAT in the Excel templates. Upload the completed files into 11taxassist for automatic processing and validation.
Review VAT Summary
The system automatically calculates Output VAT, Input VAT, and the net VAT payable or refund for the client. Review all 9 boxes, verify figures, and check for any errors before submission.
Submit to HMRC
Click Submit to HMRC — the client’s VAT return is sent digitally via the official MTD API. You receive a digital HMRC receipt with a confirmation number and time-stamped audit record.
How to Authorise Clients for MTD VAT
HMRC’s digital authorisation process replaces the traditional 64-8 paper form for MTD services. As an agent, you must request authorisation through your Agent Services Account before you can file VAT returns on a client’s behalf.
HMRC Digital Authorisation Steps
Access your HMRC ASA using your agent Government Gateway credentials.
Choose the MTD for VAT service from the available options.
HMRC generates a unique authorisation invitation link.
Share the HMRC invitation link with your client via email or secure message.
Your client logs in with their own Government Gateway and approves your authorisation request. You can now file on their behalf.
Review Each Client’s Return Before Submission
Before any return is sent to HMRC, you see a clear breakdown of every VAT box for that client. The system auto-calculates everything — no manual maths needed.
| VAT Box | Description | Amount (£) |
|---|---|---|
| Box 1 | VAT due on sales and other outputs | 2,400.00 |
| Box 2 | VAT due on acquisitions from EU | 0.00 |
| Box 3 | Total VAT due (Box 1 + Box 2) | 2,400.00 |
| Box 4 | VAT reclaimed on purchases | 1,100.00 |
| Box 5 | Net VAT to pay HMRC | £1,300.00 |
| Box 6 | Total value of sales (excl. VAT) | 12,000.00 |
| Box 7 | Total value of purchases (excl. VAT) | 5,500.00 |
| Box 8 | Total value of supplies to EU | 0.00 |
| Box 9 | Total value of acquisitions from EU | 0.00 |
HMRC-Aligned VAT Excel Templates
Download our pre-built templates for each client. Enter the figures, upload, and the system does the rest — maintaining a fully digital link as required by MTD.
VAT100 Template
Pre-formatted to match the official VAT100 return boxes (1–9). Enter output and input VAT figures directly for each client.
VAT Bookkeeping Template
Record client sales and purchases with HMRC-compliant categorisation. Supports standard and flat-rate VAT schemes.
Agent vs Individual VAT Filing
Not sure which account type you need? Here’s a quick comparison between filing as an individual and filing as an agent on behalf of clients.
| Feature | Individual | Agent |
|---|---|---|
| File own VAT returns | ||
| File VAT on behalf of clients | ||
| Manage multiple businesses | ||
| HMRC Agent Services Account required | ||
| Digital client authorisation | ||
| Excel template upload | ||
| Automatic VAT calculations | ||
| Direct HMRC MTD submission | ||
| HMRC receipt & PDF records | ||
| Price per filing | £5.99 | £5.99 |
Built for Accountants & Tax Agents
Everything you need to file MTD VAT returns for your clients with confidence — fast, secure, and fully compliant.
HMRC Recognised
Officially listed on HMRC’s recognised software directory. Submits directly via the MTD API.
Unlimited Client Management
Add and manage as many clients as you need from a single agent dashboard.
Easy Excel Upload
Upload client data via HMRC-aligned templates — no re-keying into complex forms.
Automatic Calculations
Output VAT, Input VAT, and net payable/refund calculated automatically with error checking.
Bank-Level Security
256-bit AES encryption, multi-factor authentication, and UK-only data storage.
Complete Audit Trail
HMRC receipt, confirmation number, time-stamped records, and downloadable PDFs for every submission.
Agent VAT Filing — Just £5.99 per Client Submission
No monthly subscriptions, no per-client fees. Pay only when you file. Regular price £15.99 — you save £10.00 (63% off). Each quarterly VAT return costs just £5.99 per client.
Includes HMRC-recognised software, unlimited client management, automatic calculations, error checking, direct HMRC submission, and downloadable PDF records.
Frequently Asked Questions About Online VAT Filing & MTD Self Assessment
Find answers to the most common questions about our online tax filing service.
- Keep VAT records digitally using MTD-compatible software
- Submit VAT returns electronically via an API (not the HMRC portal)
- Maintain digital links between all data sources to avoid manual entry
- Preserve digital VAT records for at least six years
- 4 Quarterly Updates (summaries of income and expenses)
- 1 Final Declaration (replaces your annual Self Assessment return)
Q2 (6 Jul – 5 Oct): due 7 November
Q3 (6 Oct – 5 Jan): due 7 February
Q4 (6 Jan – 5 Apr): due 7 May
Final Declaration: due 31 January (following year)
Ready to File Your Tax Return?
Join 1,000+ UK sole traders, landlords, and businesses who trust 11taxassist to file their VAT and Self Assessment returns securely and on time.
11taxassist Limited
14 Somerstown Court, Reading,
England, RG1 7TY.
Company number: 16416027
