MTD Guidance for bookkeepers

Bookkeepers play a vital role in ensuring clients are compliant. This guide outlines how to set up your HMRC Agent Services Account, manage authorisations, and handle the specific requirements of quarterly reporting.

Step 1: Setting up your HMRC Agent Services Account (ASA)

To act for clients under MTD, you must use an Agent Services Account (ASA). This is different from the "classic" HMRC Online Services for Agents account (Government Gateway).

• If you already have an ASA: (e.g., for MTD for VAT or the Trust Registration Service), you do not need to create a new one. You will use your existing ASA credentials.
• Linking VAT and SA: If you have existing VAT authorisations in your ASA, these remain valid. However, many bookkeepers do not have Self Assessment (SA) authorisations. To manage MTD for Income Tax, you will need to obtain specific MTD IT authorisations (see Step 2).

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Step 2: Understanding Main vs. Supporting Agent authorisation

HMRC has introduced Multi-Agent Access for MTD for Income Tax. This is a game-changer for bookkeepers who might work alongside a client's tax accountant.

If a client already has an accountant or tax-qualified bookkeeper as their "Main Agent" for Self Assessment, you can be authorised as a Supporting Agent. This allows you to handle the digital record-keeping and quarterly updates without displacing the accountant.

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Step 3: Income Streams and Separate Reporting

Under MTD for Income Tax, "qualifying income" is the total gross income (before expenses) from self-employment and property. If this exceeds £50,000 (dropping to £30,000 in April 2027), the client must join.

Crucially, different types of income require separate quarterly updates:

• Sole Trade: Each separate business requires its own quarterly update.
• UK Property: All UK rental properties are grouped into one update.
• Foreign Property: This is treated as a separate income stream and requires its own quarterly update.

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Step 4: Quarterly deadlines and calendar month alignment

Standard quarterly updates follow the tax year quarters. However, you can elect to align these to calendar months (ending on the last day of the month) to make bookkeeping simpler.

The deadline for all quarterly updates is always the 7th day of the month following the end of the standard quarter.

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Step 5: Signing up clients and software requirements

Once you are authorised, you (as either the Main or Supporting agent) can sign the client up for MTD for Income Tax.

• Software is mandatory: You must use HMRC-compatible software to keep digital records and send updates. HMRC does not provide a free tool for this.
• Sign-up process: You will need the client's National Insurance Number, Date of Birth, and business start dates for each income source.
• Digital Records: Records must be kept digitally from the start of the first MTD accounting period. Each transaction must be recorded, though summary data is what is sent in the quarterly update.

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Common pitfalls & troubleshooting

Setting up MTD IT can be finicky. Even if you are a "pro" at MTD for VAT, the Income Tax side has specific quirks that can cause errors during client onboarding or submissions.

1. The "Invisible Client" Problem

If you have linked your ASA to your old Government Gateway accounts but still can't see your SA clients, it’s likely because you have multiple legacy agent codes. You must link every old Government Gateway ID you own to the ASA to bring those existing authorisations across.

2. The "Digital Link" Rule

HMRC is strict about how data moves. Under MTD rules, "copy and paste" is officially dead. Data must flow from your bookkeeping software to HMRC via a "digital link" (API, CSV upload, or linked spreadsheets via bridging software). If you manually re-type a total from one software into a bridging tool, you are technically non-compliant.

3. Correcting Errors: No Need to Resubmit

If you spot a mistake in a previous quarter (e.g., a missed invoice in Q1 while you are in Q2), you do not need to resubmit the Q1 update. Instead:

• Correct the error in your digital records (your bookkeeping software).
• The correction will automatically be picked up in your next quarterly update.

4. Jointly Owned Property: Rules & Easements

Many clients co-own rental properties with a spouse, partner, or family member. While each owner is legally responsible for their own tax, HMRC allows some flexibility in how the data is recorded and reported.

a. One Bookkeeper, Two Taxpayers

HMRC recognises that it is impractical for two people to keep two separate sets of identical books for the same property. You can have one owner maintaining the digital records, provided that:

• The software used can split the income and expenses according to each owner’s share (usually 50/50 for spouses).
• Digital links are maintained so that the data flows to both owners’ individual MTD submissions without manual re-keying.

b. Quarterly Update Options

If your client has jointly let properties, they have a choice on how to handle the quarterly updates. They can choose to include either:

• Full Details: Both the property income and their share of the expenses.
• Income-Only: Just their share of the property income, excluding expenses for those specific joint properties.

c. Mixed Portfolios (Sole & Joint)

The "Income-Only" easement only applies to the jointly owned properties. If a client owns some properties alone and others jointly, their quarterly updates must still include:

• The income from the joint properties.
• Both the income and the expenses for the properties they solely own.

This allows bookkeepers to focus on getting the "gross" figures right every three months, leaving the complex expense apportionments for the year-end reconciliation if needed.

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Struggling with your ASA Setup?

Setting up an Agent Services Account (ASA) should be a straightforward process, but technical glitches or "stuck" applications can happen. If you have followed the HMRC guidance and your account is not active within the timeframe they initially specified, do not let it stall your MTD preparations.

When contacting the ICB for help with your ASA, please ensure you have the following ready:

• Your ICB Practice Licence number.
• The date you submitted your ASA application.
• Any submission reference numbers or correspondence received from HMRC.

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