The Landlord’s Tax Journey: Your Guide to Filing Landlord Tax with SA105 and SA106

You never expected to become a landlord. Maybe you inherited a property, maybe you moved in with your partner and decided to rent out your flat, or maybe you saw an opportunity to invest and took the plunge. Regardless of how you ended up here, one thing has become crystal clear: filing landlord tax is not just a formality—it’s a financial responsibility that demands your attention.

filing landlord tax- By Taxduk

Now, you're navigating through rental agreements, tenant queries, maintenance issues, and suddenly HMRC expects you to understand SA105 and even SA106. It feels overwhelming. But it doesn’t have to be. This is your guide—clear, precise, and grounded in what really matters to landlords like you.

Chapter 1: Understanding Your Tax Obligation as a Landlord

As a UK landlord, you’re legally required to report your rental income to HMRC. It doesn’t matter if you’re renting out a single room or managing a portfolio of properties. The moment you earn income from property, you step into the world of Self Assessment—the system through which HMRC collects tax from individuals with complex income streams.

You’re probably already familiar with the standard tax return, but for landlords, there’s a twist: you need to file SA105—a supplementary page specifically for declaring income from UK property. If you’ve got income from overseas property or foreign investments tied to your rental activities, that’s when SA106 enters the picture.

Chapter 2: The SA105 Form — Your Property Income Companion

Here’s where the tax jargon meets real-life relevance. The SA105 form is your key to correctly filing landlord tax. You’ll use this form to report income from:

• Residential property lettings

• Holiday lettings (if in the UK)

• Commercial lettings

• Renting out rooms in your own home (above the Rent a Room threshold)

Read More:- How Far Back Can HMRC Investigate Your Self Assessment Tax Returns?

Let’s break this down in terms of your journey. Imagine you've been renting out a two-bedroom flat in Birmingham for £1,200 a month. Over the tax year, that’s £14,400 in gross rental income. You’ve had expenses—agent fees, repairs, insurance, and maybe mortgage interest.

On SA105, you’ll:

• Declare gross rental income

• Deduct allowable expenses (maintenance, insurance, management fees, etc.)

• Arrive at your taxable rental profit

That final figure is what HMRC will use to determine how much tax you owe.

But this isn’t just paperwork—it’s about strategy. Every line in SA105 is an opportunity to get your taxes right or wrong. And with penalties for mistakes, underreporting, or missing deadlines, accuracy is non-negotiable.

Chapter 3: Expenses, Reliefs, and Smart Landlord Decisions

Here’s where it gets interesting. Filing your landlord tax isn’t just about declaring income—it’s also about claiming legitimate expenses and reliefs to reduce your tax bill. But not all expenses are created equal.

Let’s say you replaced the worn-out carpets in your rental flat. That’s a maintenance expense—allowable. But if you upgraded the kitchen with high-end fittings, that’s likely a capital expense, which is only deductible when you sell the property.

Common allowable expenses on SA105 include:

• Letting agent fees

• Council tax and utility bills (if paid by you)

• Property maintenance and repairs

• Buildings and contents insurance

• Legal and accountancy fees related to the rental

Knowing the difference between allowable and disallowable expenses is essential. If you overclaim, HMRC might hit you with penalties. Underclaim, and you’re simply overpaying your tax.

It pays—literally—to keep receipts, records, and a detailed log of every transaction.

Chapter 4: SA106 — When International Income Joins the Mix

Not every landlord is UK-only. Perhaps you've invested in a holiday rental in Spain or have foreign dividends that affect your tax calculation. In these scenarios, SA106, the Foreign Income page, becomes part of your Self Assessment.

The SA106 form lets you declare:

• Foreign property rental income

• Foreign dividends or interest

• Double taxation relief (so you’re not taxed twice on the same income)

Imagine this: you’re renting out a small apartment in Portugal. You’re taxed locally there, but as a UK resident, you must also declare that income in the UK. On SA106, you’ll declare the foreign rental income and claim Foreign Tax Credit Relief to ensure you don’t pay tax twice on the same earnings.

This is where landlord tax becomes not just an administrative task but a cross-border financial exercise. Getting it wrong means either overpaying or inviting an HMRC inquiry.

Chapter 5: Digital Records and Making Tax Digital (MTD)

If you’re a digitally savvy landlord—or want to be—you’ll want to stay ahead of Making Tax Digital (MTD). Though MTD for Income Tax has been delayed to 2026 for most landlords, those earning above £50,000 annually will need to comply first.

Under MTD, you’ll:

• Maintain digital records of income and expenses

• Use compatible software to submit updates to HMRC every quarter

• Submit a final declaration annually

While it might sound like more work, MTD is designed to reduce errors and streamline the tax process. If you're already using tools like Xero, QuickBooks, or Landlord Vision, you’re on the right path. If not, it's time to consider a shift to digital.

This isn’t about the future anymore—it’s your tax present evolving.

Chapter 6: Common Pitfalls When Filing Landlord Tax

Here’s what could trip you up:

• Missing deadlines: The Self Assessment deadline is 31 January for online returns. Miss it, and you face penalties.

• Incorrect expense claims: Claiming personal expenses (like your own home’s broadband) on your rental property tax return is a red flag.

• Forgetting to report part-year income: If you only rented out the property for part of the year, don’t prorate incorrectly.

• Misclassifying furnished holiday lets (FHLs): These have specific rules and reliefs that differ from regular lets. Know the difference.

Each of these mistakes can result in HMRC raising eyebrows—or worse, audits. But they’re avoidable with diligence, clarity, and correct use of SA105 and SA106.

Read More:- Can I claim tax relief for working from home (WFH)?

Chapter 7: What If You’ve Never Filed Before?

Let’s say you’re reading this and thinking, “I’ve been renting out my property for two years and never told HMRC.” That’s a common scenario—and it’s not too late.

You need to:

1. Register for Self Assessment immediately (via your Government Gateway account).

2. Declare past rental income via a voluntary disclosure or through previous tax returns.

3. Be honest—HMRC’s Let Property Campaign encourages landlords to come clean, often with reduced penalties.

It’s better to act now than wait until HMRC catches on. They’re using increasingly sophisticated digital tools to spot undeclared rental income.

Chapter 8: Filing the Return — Step by Step

When it’s time to file, here’s your game plan:

1. Log into your HMRC online account.

2. Choose ‘Complete your tax return’.

3. Fill in your general income and details.

4. Add SA105 (UK property income) and SA106 (if applicable).

5. Double-check all figures.

6. Submit before the 31 January deadline.

You’ll receive confirmation and, shortly after, your final tax bill. Pay it before the payment deadline (also 31 January) to avoid interest and penalties.

It sounds straightforward because it is—when you’re prepared.

Chapter 9: When to Get Help

There’s no shame in asking for help. In fact, it’s often the smart move. Consider hiring a tax adviser or accountant if:

• You have multiple properties

• You own properties in different countries

• You’re unsure about expenses

• You’re filing late or amending a previous return

A professional can ensure your SA105 and SA106 are watertight and save you from costly mistakes. But even if you go it alone, staying informed is your best tool.

Final Chapter: Filing Landlord Tax Is More Than Compliance—It’s Smart Ownership

Here’s the truth: filing landlord tax correctly isn’t just about staying on the right side of HMRC—it’s about taking ownership of your financial future. It’s knowing where your money goes, how your investment performs, and how to optimize your returns legally.

With the right mindset, accurate records, and a clear understanding of SA105 and SA106, you transform tax season from a source of stress into a moment of clarity and control.

Because being a landlord isn’t just about bricks and tenants—it’s about building wealth. And filing your taxes properly is part of that foundation.

Now it’s your turn. You’ve read the guide. You understand the forms. You know the pitfalls. So grab your records, log into HMRC, and take charge of your landlord journey.