What online portals do tax advisors use for HMRC submissions?

Understanding HMRC Online Portals for Tax Advisors in 2025

The digital transformation of tax administration in the UK has revolutionized how tax advisors manage submissions to HM Revenue & Customs (HMRC). As of February 2025, online portals have become the cornerstone of efficient tax compliance for self-employed individuals, businesses, and tax advisors. These platforms streamline processes like Self Assessment, VAT returns, Corporation Tax, and PAYE submissions, ensuring accuracy and compliance with HMRC regulations. For UK taxpayers and business owners, understanding which portals tax advisors use is crucial for choosing the right professional or software to manage their tax affairs. This first part explores the primary HMRC online portals, their functionalities, key statistics, and why they matter for tax advisors in 2025.

The Role of HMRC Online Services in Tax Submissions

HMRC Online Services is the central digital platform for tax advisors, replacing the older Government Gateway in 2019. It serves as a hub where tax advisors can access a range of services, including Self Assessment, VAT, PAYE for employers, and Corporation Tax. According to GOV.UK, as of February 2025, over 11.5 million taxpayers filed their Self Assessment tax returns for the 2023/24 tax year using HMRC Online Services by the January 31, 2025 deadline, with 97.36% (11,205,810) submitted online, highlighting the dominance of digital submissions. This platform requires advisors to set up a personal or business tax account, which involves verifying identity through the Government Gateway or the newer One Login for Government system, designed for enhanced accessibility and security.

For professional tax advisors in London , HMRC Online Services offers a secure environment to manage client data, submit returns, and make payments. Advisors must register as agents to access client accounts, using an Agent Government Gateway ID. In 2025, HMRC reported that 732,498 returns were filed on the deadline day alone, with peak filing between 4:00 PM and 4:59 PM (58,517 submissions), underscoring the platform’s critical role during peak tax seasons. The platform supports multiple tax types, including:

• Self Assessment: Used by sole traders, partners, and individuals with untaxed income to report earnings and calculate tax liabilities. The online filing deadline is midnight on January 31, 2026, for the 2024/25 tax year.
• VAT: Mandatory for businesses with a turnover above £90,000, requiring quarterly submissions via Making Tax Digital (MTD)-compliant software integrated with HMRC Online Services.
• Corporation Tax: For limited companies, with 541 software packages listed by HMRC for VAT and Corporation Tax submissions as of August 2024.
• PAYE for Employers: Facilitates payroll tax submissions and benefits-in-kind reporting, with mandatory payrolling set to begin in April 2027.

Key Features of HMRC Online Services for Advisors

Tax advisors rely on HMRC Online Services for its robust features, which include:

• Personal Tax Account (PTA): Allows advisors to manage client records, check tax codes, update personal details, and claim refunds. In 2025, the PTA is accessible via the HMRC app, which saw increased usage with nearly 300,000 customers filing early for the 2024/25 tax year.
• Agent Services Account: Enables advisors to act on behalf of clients, accessing services like Self Assessment and VAT. HMRC’s Agent Query Resolution Service, launched on March 31, 2025, allows advisors to escalate unresolved queries via an online form, improving efficiency.
• Digital Assistant and Webchat: Advisors can use HMRC’s digital assistant for quick guidance or connect to live webchat for complex queries, available Monday to Saturday, 8 AM to 8 PM, reducing reliance on phone support.

Case Study: A Tax Advisor’s Experience with HMRC Online Services

Consider Sarah, a tax advisor in Manchester managing 50 small business clients. In January 2025, she used HMRC Online Services to file Self Assessment returns for 45 clients, leveraging the platform’s ability to handle bulk submissions. By integrating MTD-compliant software like Xero, she ensured VAT returns were submitted seamlessly for her retail clients. Sarah also used the Agent Services Account to check a client’s tax code, correcting an error that saved the client £1,200 in overpaid tax. However, she faced delays in resolving a PAYE query, prompting her to use the new Agent Query Resolution Service form, which provided a response within 20 working days. This real-life example illustrates how HMRC Online Services streamlines tasks but requires advisors to stay updated on new tools and deadlines.

The Shift to Making Tax Digital (MTD)

Making Tax Digital is a key component of HMRC’s digital strategy, mandating digital record-keeping and submissions for VAT, Income Tax, and eventually Corporation Tax. As of April 2026, self-employed individuals and landlords with income over £50,000 must use MTD-compliant software for quarterly Income Tax updates, extending to those over £30,000 by April 2027. HMRC lists 433 providers of MTD-compliant software for VAT, with 198 bridging packages to convert spreadsheet data into HMRC-compatible formats. Tax advisors must ensure clients use software that generates XML streams with an IRmark (a unique reference for return authenticity), as paper-like submissions are not accepted.

Statistics Highlighting Digital Adoption

• VAT Submissions: All VAT-registered businesses must use MTD, with 541 software packages available, including 20 offering free or trial versions.
• Self Assessment Penalties: In 2025, an estimated 1.1 million taxpayers missed the Self Assessment deadline, facing penalties starting at 3% of tax owed for up to 15 days late.
• HMRC App Usage: The HMRC app supports PTA access, with downloads increasing as taxpayers seek mobile solutions for tax management.
• Call Wait Times: HMRC’s phone support answered only 66.4% of calls in 2023/24, pushing advisors toward online portals for faster service.

Why Tax Advisors Prefer Online Portals

Online portals reduce administrative burdens, allowing advisors to manage multiple clients efficiently. The integration of commercial software like QuickBooks, FreeAgent, or Sage with HMRC Online Services ensures compliance and minimizes errors. For instance, advisors can use these tools to automate VAT calculations, reducing the risk of penalties, which can reach 10% of tax owed after 31 days of late submission. The transition to One Login for Government by 2026 will further simplify access, replacing the Government Gateway and supporting international IDs for enhanced security.

This part has outlined the foundational role of HMRC Online Services and MTD in tax submissions, supported by recent statistics and a real-life case study. The next part will delve into specific commercial software solutions tax advisors use to complement HMRC portals, offering practical insights for taxpayers and businesses.

Commercial Software Solutions for HMRC Submissions

The reliance on HMRC Online Services is only part of the equation for tax advisors in 2025. To enhance efficiency and ensure compliance with HMRC’s Making Tax Digital (MTD) initiative, tax advisors increasingly integrate commercial software solutions with HMRC portals. These tools automate calculations, streamline data management, and provide user-friendly interfaces for both advisors and their clients. This part explores the most popular commercial software options used by UK tax advisors, their features, benefits, and real-world applications, supported by recent data and a case study to help taxpayers and business owners make informed choices.

Popular Commercial Software for HMRC Submissions

Tax advisors use a variety of MTD-compliant software to facilitate HMRC submissions, with 541 software packages listed by HMRC for VAT and Corporation Tax as of August 2024. Below are the leading options, their key features, and how they integrate with HMRC Online Services:

• Xero: A cloud-based accounting platform widely used by tax advisors for its seamless integration with HMRC for VAT, Self Assessment, and PAYE. Xero automates VAT calculations and submissions, with 433 providers offering MTD-compliant versions. It’s particularly popular for small businesses, with a user base of over 700,000 UK subscribers in 2024, according to Xero’s official reports. Advisors like its real-time financial tracking and client collaboration tools.
• QuickBooks: Known for its intuitive interface, QuickBooks supports MTD for VAT and Income Tax, allowing advisors to manage client accounts, generate XML streams for HMRC, and track expenses. In 2025, QuickBooks reported that 60% of its UK users were small businesses submitting VAT returns digitally, reflecting its widespread adoption.
• Sage: A robust solution for larger businesses and advisors handling complex accounts, Sage offers MTD-compliant modules for VAT, Corporation Tax, and payroll. Sage’s cloud platform supports 198 bridging packages, enabling advisors to convert spreadsheet data into HMRC-compatible formats. Its scalability makes it ideal for advisors with diverse client portfolios.
• FreeAgent: Tailored for freelancers and small businesses, FreeAgent simplifies Self Assessment and VAT submissions. It’s used by over 150,000 UK businesses in 2025, with features like automated tax calculations and direct HMRC filing. FreeAgent’s mobile app enhances accessibility for advisors on the go.
• TaxCalc: A specialist tool for tax advisors, TaxCalc focuses on tax return preparation and compliance, supporting Self Assessment, Corporation Tax, and partnership returns. It’s praised for its detailed reporting and integration with HMRC’s Agent Services Account, used by 20% of UK accountancy firms in 2024, per industry surveys.

Benefits of Commercial Software for Advisors

These software solutions offer several advantages over manual processes or HMRC’s basic portal:

• Automation: Tools like Xero and QuickBooks automate VAT calculations, reducing errors. For example, a 2024 study by the Chartered Institute of Taxation (CIOT) found that MTD-compliant software reduced VAT filing errors by 30% compared to manual submissions.
• Time Efficiency: Advisors can manage multiple clients simultaneously, with Sage reporting that its users save an average of 10 hours per month on tax-related tasks.
• Compliance: Software ensures submissions meet HMRC’s XML and IRmark requirements, avoiding penalties. In 2025, late Self Assessment submissions incurred penalties starting at 3% of tax owed for up to 15 days late, escalating to 10% after 31 days.
• Client Collaboration: Platforms like FreeAgent allow clients to upload receipts and invoices, streamlining data collection. This is critical as HMRC requires detailed records, with 1.1 million taxpayers facing penalties for late filings in 2025.

Case Study: Streamlining Submissions with QuickBooks

Take John, a tax advisor in Birmingham managing 30 clients, including sole traders and limited companies. In 2025, he switched to QuickBooks to handle VAT and Self Assessment submissions after struggling with manual spreadsheets. For a client running a retail business with £120,000 annual turnover, John used QuickBooks to automate VAT calculations, submitting quarterly returns via MTD in under 30 minutes. The software’s integration with HMRC Online Services ensured compliance, and its dashboard helped John identify a £2,000 expense deduction missed by the client, reducing their tax liability. When a PAYE query arose, John used the HMRC Agent Services Account to escalate it via the new query resolution form, receiving a response within 15 working days. This case highlights how commercial software enhances efficiency and accuracy for advisors.

Choosing the Right Software for Your Needs

Selecting the appropriate software depends on the client’s business size and tax requirements:

• Sole Traders and Freelancers: FreeAgent or Xero are ideal for simplicity and affordability, with FreeAgent offering plans starting at £10/month for basic Self Assessment support.
• Small Businesses: QuickBooks and Xero excel for VAT and payroll, with QuickBooks offering a 30-day free trial used by 25% of new UK users in 2024.
• Larger Businesses: Sage is preferred for its scalability, supporting complex Corporation Tax filings for companies with turnovers above £1 million.
• Specialist Advisors: TaxCalc is favored for its focus on tax compliance, used by advisors handling trusts and partnerships.

Integration with HMRC Portals

All these software solutions integrate with HMRC Online Services via APIs, ensuring seamless data transfer. For example, Xero’s MTD bridge allows advisors to submit VAT returns directly from the platform, with 97.36% of Self Assessment returns filed online in 2025. Advisors must ensure software meets HMRC’s testing standards, as outlined by the Software Developer Service team, which reviews XML outputs for compliance. The transition to One Login for Government by March 2026 will further streamline access, requiring advisors to update their credentials.

Statistics on Software Adoption

• Software Providers: HMRC lists 433 MTD-compliant software providers for VAT and 198 bridging packages, with 20 offering free versions.
• User Growth: Xero reported a 15% increase in UK users from 2023 to 2024, driven by MTD mandates.
• Error Reduction: MTD-compliant software reduced VAT errors by 30%, per CIOT’s 2024 study.
• Mobile Access: The HMRC app, integrated with software like FreeAgent, saw a 20% increase in downloads in 2025, reflecting mobile tax management trends.

Challenges and Considerations

While commercial software enhances efficiency, advisors face challenges like learning curves and costs. For instance, Sage’s advanced plans can cost £50/month, which may be prohibitive for small firms. Additionally, HMRC’s closure of its online accounts and tax filing service by March 31, 2026, requires advisors to transition to MTD-compliant software early to avoid disruptions. Advisors must also ensure clients maintain digital records, as HMRC’s MTD rules mandate digital record-keeping for VAT and Income Tax by 2026/27.

This part has detailed the commercial software solutions tax advisors use to complement HMRC portals, offering practical insights and a case study. The next part will explore best practices for taxpayers and businesses working with advisors, including tips to maximize efficiency and avoid common pitfalls.

Best Practices for Taxpayers and Businesses Using Advisors for HMRC Submissions

For UK taxpayers and business owners, working with a tax advisor who leverages online portals and commercial software can simplify HMRC submissions and ensure compliance. However, maximizing the benefits of these tools requires collaboration, preparation, and awareness of best practices. This final part provides actionable advice for taxpayers and businesses, covering how to work effectively with advisors, avoid common pitfalls, and prepare for upcoming changes like the full rollout of Making Tax Digital (MTD). Supported by recent statistics and a case study, this section empowers readers to navigate the tax submission process confidently in 2025.

Collaborating with Your Tax Advisor

Effective collaboration with a tax advisor starts with clear communication and organized records. Here are key steps taxpayers and businesses should take:

• Provide Complete Records: Advisors rely on accurate data for submissions. For Self Assessment, this includes bank statements, receipts, and details of untaxed income like dividends or rental income. HMRC reported that 11,509,810 Self Assessment returns were filed by January 31, 2025, with errors in 5% due to incomplete records.
• Use Digital Tools: Share data via cloud-based platforms like Xero or FreeAgent, which allow real-time updates. For example, uploading receipts to FreeAgent’s mobile app can reduce data entry time by 40%, according to a 2024 user survey.
• Understand Deadlines: The online Self Assessment deadline is January 31, 2026, for the 2024/25 tax year, with paper filings due by October 31, 2025. Missing these incurs penalties starting at 3% of tax owed for up to 15 days late. Advisors can set reminders, but clients must provide timely information.
• Authorize Agent Access: Grant your advisor access via an Agent Government Gateway ID. In 2025, HMRC’s Agent Services Account processed 20% more client authorizations than in 2024, streamlining submissions.

Avoiding Common Pitfalls

Taxpayers often face challenges that advisors can help mitigate, but awareness is key:

• Late Filings: In 2025, 1.1 million taxpayers missed the Self Assessment deadline, facing penalties up to 10% of tax owed after 31 days. Advisors using MTD-compliant software can automate reminders to avoid this.
• Incorrect Tax Codes: A 2024 ICAEW report noted that 15% of PAYE taxpayers had incorrect tax codes, leading to overpayments. Advisors can check codes via the Personal Tax Account (PTA), as seen in Sarah’s case in Part 1.
• Non-Compliance with MTD: All VAT-registered businesses must use MTD, and from April 2026, self-employed individuals with income over £50,000 will follow suit. Non-compliance can lead to audits, with HMRC conducting 10% more MTD compliance checks in 2024 than 2023.
• Overlooking Reliefs: Advisors can identify tax reliefs, such as Gift Aid. For example, a 40% taxpayer can reclaim £25 per £100 donated, a benefit missed by 30% of eligible taxpayers in 2024, per Moore Kingston Smith.

Case Study: A Small Business Navigating MTD with an Advisor

Lisa, a café owner in Bristol with a £95,000 turnover, struggled with VAT compliance in 2024. Her advisor, Emma, recommended switching to Sage for MTD-compliant VAT submissions. Emma set up Lisa’s digital records, linking Sage to HMRC Online Services for quarterly filings due by May 7, 2025, for the period ending March 31. By automating VAT calculations, Emma reduced Lisa’s filing time from 5 hours to 1 hour per quarter. When Lisa received a notice for a Self Assessment return due to additional rental income, Emma used TaxCalc to file it online by January 31, 2025, claiming £1,500 in expense reliefs. Emma also used the HMRC app to check Lisa’s PTA, ensuring her tax code reflected her dual income sources. This case underscores the importance of advisor expertise and software in navigating complex tax obligations.

Preparing for Future Changes

The tax landscape is evolving, and taxpayers must prepare for:

• MTD Rollout: By April 2027, self-employed individuals and landlords with income over £30,000 must use MTD for Income Tax, requiring quarterly updates via software like QuickBooks. Advisors can help set up digital record-keeping early.
• One Login for Government: Replacing the Government Gateway by March 2026, this system will use biometric IDs for enhanced security. Advisors are preparing clients for this transition, with 10% of agents already testing One Login in 2025.
• HMRC Service Closure: HMRC’s online accounts and tax filing service will close by March 31, 2026, requiring all users to adopt MTD-compliant software. Early adoption is critical, as 20% of sole traders were unprepared in a 2025 survey.

Tips for Choosing a Tax Advisor

Selecting the right advisor ensures effective use of online portals:

• Check MTD Expertise: Ensure the advisor is familiar with MTD-compliant software. A 2024 CIOT survey found that 85% of advisors use at least one MTD tool like Xero or Sage.
• Verify Credentials: Look for affiliations with ICAEW or CIOT, as seen in HMRC’s Agent Query Resolution Service guidelines.
• Assess Communication: Choose advisors offering digital collaboration tools. For example, FreeAgent’s client portal, used by 150,000 UK businesses, enhances advisor-client interaction.
• Cost Transparency: Advisor fees vary, with small firms charging £500–£2,000 annually for Self Assessment and VAT services, per a 2025 TaxAid report.

Statistics on Tax Compliance

• Digital Filing Dominance: 97.36% of Self Assessment returns were filed online in 2025, with only 304,000 paper returns.
• MTD Adoption: 100% of VAT-registered businesses use MTD, with 433 software providers supporting compliance.
• Penalty Costs: Late filings cost taxpayers £100 million in penalties in 2025, emphasizing the need for advisor support.
• Advisor Usage: 60% of UK small businesses use tax advisors for HMRC submissions, per a 2024 Sage survey.

This part has provided practical guidance for taxpayers and businesses, supported by a case study and recent data, ensuring a user-friendly and SEO-optimized approach. Together, these three parts offer a comprehensive guide to the online portals and tools tax advisors use for HMRC submissions in 2025, empowering readers to make informed decisions.