CIS Subcontractors: Your MTD Software Guide for April 2026

Published: 25 February 2026 | Reading time: 25 minutes

If you're a construction subcontractor registered under CIS (Construction Industry Scheme) and earning £50,000+ per year, 6 April 2026 is a deadline you can't ignore. Making Tax Digital (MTD) for Income Tax becomes mandatory, and you'll need software that handles both CIS deductions tracking AND quarterly digital submissions to HMRC.

This isn't about buying two separate tools. This guide shows you which MTD-compatible software actually understands CIS, how to choose the right one, and what happens if you miss the deadline.

Why CIS Subcontractors Need Special MTD Considerations

Let's start with what makes your situation unique:

1. CIS Deductions Complicate Your Tax Position

Under CIS, contractors deduct either:

• 20% if you're registered (net payment status)
• 30% if you're not registered (gross deductions)

These deductions are advance payments toward your tax and National Insurance bill. Your MTD software needs to:

• Track CIS deductions from each contractor
• Match them against your actual tax liability
• Calculate whether you're owed a refund or owe more tax
• Submit this data digitally to HMRC every quarter

Generic accounting software (designed for retail, freelancers, or service businesses) often treats CIS deductions as "other income" or fails to reconcile them properly. This creates a mess at year-end.

2. Multiple Contractors = Multiple CIS Statements

If you work for 5 different contractors in a year, you receive 5 separate CIS statements showing deductions. Your MTD software needs to:

• Import or manually log all CIS statements
• Aggregate total deductions across contractors
• Reconcile against invoices issued
• Flag discrepancies (e.g., contractor reported wrong gross amount)

This isn't a "nice to have" — it's mandatory for accurate quarterly submissions.

3. Quarterly Updates Require Real-Time CIS Tracking

Under MTD, you'll submit updates to HMRC four times per year:

• 6 July 2026 (covering 6 Apr – 5 Jul)
• 6 October 2026 (covering 6 Jul – 5 Oct)
• 6 January 2027 (covering 6 Oct – 5 Jan)
• 6 April 2027 (covering 6 Jan – 5 Apr)

Each submission includes:

• Total business income (gross amounts before CIS deductions)
• Allowable expenses
• CIS deductions made by contractors
• Provisional tax calculation

If your software doesn't auto-populate CIS deductions from your invoices and statements, you'll be manually entering data four times a year. That's error-prone and time-consuming.

What MTD for Income Tax Actually Means for You

Who's Required to Use MTD from 6 April 2026?

You're in scope if you meet all three criteria:

1. Self-employed or in a partnership (sole traders, limited company directors taking dividends, partners)
2. Income from self-employment or property over £50,000 per year (before CIS deductions)
3. Submit a Self-Assessment tax return

Critical point for CIS subcontractors: The £50,000 threshold is your gross income (before contractors deduct 20-30%). If you invoiced £55,000 but received £44,000 after 20% CIS deductions, you're still over the threshold — MTD applies to you.

What You're Required to Do

Starting 6 April 2026, you must:

1. Keep digital records of all business income and expenses using MTD-compatible software
2. Submit quarterly updates to HMRC via the software (not manual spreadsheets)
3. Submit a final End of Period Statement (EOPS) by 31 January after the tax year ends
4. File your final Self-Assessment return as usual (MTD doesn't replace this — it adds to it)

What Happens If You Don't Comply?

HMRC penalties for MTD non-compliance:

For CIS subcontractors, the biggest risk is not claiming CIS deductions properly in quarterly submissions, leading to overpaid tax that you have to claim back later (or lose entirely).

MTD Software That Actually Handles CIS Properly

Not all MTD-compatible software is created equal when it comes to CIS. Here's what to look for:

Essential CIS Features

Top MTD Software Options for CIS Subcontractors (2026)

1. Xero (Most Popular)

Price: £14/month (Early plan) to £38/month (Established)

CIS features:

• ✅ CIS deduction tracking (automatic or manual entry)
• ✅ Multi-contractor statements
• ✅ MTD quarterly submissions via built-in bridge
• ✅ Reverse charge VAT support
• ❌ No CIS300 contractor returns (use HMRC online instead)

Best for: Subcontractors who also run their own business (multiple income streams), need strong invoicing, and want bank feed automation.

Downsides: Steeper learning curve than simpler tools. Overwhelming if you just need CIS + MTD basics.

2. QuickBooks Self-Employed

Price: £6/month (basic) to £18/month (premium)

CIS features:

• ✅ CIS deduction entry (manual)
• ✅ Quarterly MTD submissions
• ✅ Mileage tracking (common for construction workers)
• ⚠️ Limited multi-contractor reconciliation (basic only)
• ❌ No CIS300 support

Best for: Solo subcontractors with 1-2 main contractors, want low cost, don't need advanced features.

Downsides: CIS tracking is manual (no auto-import from statements). Fine if you have simple setup, painful if you juggle 5+ contractors.

3. FreeAgent

Price: £19/month (includes MTD + Self-Assessment filing)

CIS features:

• ✅ Full CIS support (considered gold standard for UK freelancers)
• ✅ CIS deduction reconciliation against tax bill
• ✅ Handles both subcontractor AND contractor CIS (if you hire others)
• ✅ MTD quarterly submissions + final return
• ✅ Built-in Self-Assessment filing (saves accountant fees)

Best for: Subcontractors who want "set and forget" — comprehensive CIS handling, includes SA filing, great support.

Downsides: More expensive than basic options. Overkill if you only need MTD compliance and already have an accountant.

4. Sage Business Cloud Accounting

Price: £14/month (Accounting Start) to £32/month (Accounting Plus)

CIS features:

• ✅ CIS deduction tracking
• ✅ MTD submissions
• ✅ Strong invoicing (if you issue CIS invoices to contractors)
• ⚠️ CIS setup requires understanding chart of accounts (less beginner-friendly)

Best for: Subcontractors with accounting experience, want established brand, need robust reporting.

Downsides: Interface feels dated compared to Xero/FreeAgent. Learning curve for CIS-specific setup.

5. Pandle (Free Option)

Price: Free (ad-supported) or £5/month (Premium, removes ads)

CIS features:

• ✅ Basic CIS deduction entry
• ✅ MTD submissions (via bridging software, £2-5/month extra)
• ⚠️ Very manual — no automation
• ❌ No multi-contractor reconciliation tools

Best for: Absolute budget option. Works if you have 1 contractor, simple income/expenses, don't mind manual data entry.

Downsides: You get what you pay for. Fine for compliance, frustrating for efficiency.

Which One Should You Choose?

Quick decision tree:

• 1-2 contractors, low income variability, tight budget? → QuickBooks Self-Employed (£6/month)
• Multiple contractors, want full CIS reconciliation, don't mind paying for quality? → FreeAgent (£19/month)
• Need invoicing + expenses + bank feeds + scalability? → Xero (£14/month)
• Absolutely zero budget? → Pandle Free (but budget £2-5/month for MTD bridge)

Step-by-Step: Setting Up MTD Software for CIS

Regardless of which software you choose, here's the process:

Step 1: Sign Up for MTD (Before 6 April 2026)

1. Go to HMRC's MTD sign-up page
2. You'll need your UTR (Unique Taxpayer Reference) and National Insurance number
3. HMRC will send a confirmation code by post (takes 7-10 days — don't leave this to late March!)
4. Once confirmed, you're registered for MTD

Deadline to sign up: Technically any time before your first quarterly deadline (6 July 2026), but sign up by early March 2026 to avoid last-minute postal delays.

Step 2: Choose and Purchase Your Software

Most MTD software offers free trials (7-30 days). Use this to:

• Test CIS deduction entry workflow
• Import a few months of real data
• Check if reconciliation makes sense
• Contact support with CIS-specific questions

Don't commit until you've confirmed the software actually handles your CIS setup properly.

Step 3: Configure CIS Settings

In your chosen software:

1. Add each contractor as a "customer" or "income source" (depending on software terminology)
2. Set CIS deduction rate (20% if registered, 30% if not)
3. Link to your CIS statements (some software imports from HMRC API, others require manual entry)
4. Create income categories for different work types (labour, materials, plant hire, etc.)
5. Set up expense tracking for allowable costs (tools, vehicle, insurance, etc.)

Step 4: Backfill Data (If Starting Mid-Year)

If you're setting up in, say, August 2026 (after 6 April), you need to:

• Enter all income since 6 April 2026
• Enter all expenses since 6 April 2026
• Enter all CIS deductions from contractors since 6 April 2026

This ensures your first quarterly submission (which is already late) is accurate.

Pro tip: Start in January-March 2026 so 6 April = clean slate. No backfilling needed.

Step 5: Link to HMRC

Your software will have an "Authorise with HMRC" or "MTD Setup" section. This:

• Connects your software to your MTD account
• Allows the software to submit on your behalf
• Pulls down your CIS verification status (if supported)

You'll be redirected to HMRC's Government Gateway login, approve access, then return to the software.

Step 6: Submit Your First Quarterly Update (6 July 2026)

When July comes, your software will:

1. Automatically calculate income, expenses, and CIS deductions for 6 Apr – 5 Jul
2. Generate the quarterly submission
3. Let you review before sending
4. Submit to HMRC digitally
5. Provide confirmation + reference number

The whole process takes 5-10 minutes if your data's been entered regularly. Takes hours if you've left it all to the last day.

Common CIS + MTD Mistakes to Avoid

1. Not Recording Gross Amounts Before CIS Deductions

Wrong: You invoice £1,000, receive £800 after 20% CIS, record income as £800.

Right: Record £1,000 as income, £200 as "CIS deduction (tax paid on account)".

Why it matters: HMRC needs gross income for MTD submissions. If you only record net amounts, your quarterly updates will be wrong and you'll be flagged for underdeclared income.

2. Forgetting to Claim CIS Deductions in Quarterly Updates

CIS deductions are advance tax payments. If you don't claim them in your quarterly submissions, HMRC will calculate tax as if you haven't paid anything yet.

Example:

• Gross income Q1: £15,000
• CIS deductions: £3,000 (20%)
• You received: £12,000

If you forget to claim the £3,000, HMRC will calculate tax on £15,000 as if you owe the full amount. You'll either overpay or have to claim a refund later (hassle).

3. Mixing Up CIS Deductions and VAT

CIS deductions are not VAT. They're income tax and National Insurance paid in advance.

If you're VAT registered:

• CIS deductions apply to the labour portion of your invoice
• Materials are usually exempt from CIS (but subject to reverse charge VAT rules)
• Your MTD software needs to handle both separately

This is why "CIS-aware" software matters — generic tools conflate these.

4. Assuming MTD Replaces Self-Assessment

MTD adds to Self-Assessment, it doesn't replace it.

You still need to:

• File your final SA return by 31 January (deadline unchanged)
• Pay any additional tax owed by 31 January (after CIS deductions are reconciled)
• Claim refunds if CIS deductions exceeded your final tax bill

MTD quarterly updates are progress reports. Self-Assessment is the final reckoning.

5. Waiting Until March 2026 to Sort This Out

If you sign up for MTD in late March, you'll hit these problems:

• HMRC confirmation code arrives after 6 April = can't submit first quarter on time
• Software free trials expire before you've properly tested CIS setup
• Support teams swamped with last-minute panic requests = slow responses

Start now. Even if 6 April feels far away, setting up MTD software + testing CIS tracking takes 2-4 weeks to get right.

What If You're Under £50k But Close?

If you're earning £45k-£50k and expect growth in 2026-27, consider:

1. Voluntary early adoption — sign up for MTD even if not required. Gets you ahead of the curve for when you do cross £50k.
2. Choose MTD-compatible software now — even if just for expenses tracking. When MTD becomes mandatory, you're already set up.
3. Monitor your income quarterly — if you cross £50k mid-year, you're required to join MTD from the next tax year (6 April 2027).

Final Checklist: Are You MTD-Ready for CIS?

Use this to assess your readiness:

If you've ticked all boxes by March 2026, you're ahead of 80% of CIS subcontractors.

Key Takeaways

• CIS subcontractors earning £50k+ (gross) must use MTD software from 6 April 2026
• Not all MTD software handles CIS properly — choose one with multi-contractor tracking and deduction reconciliation
• FreeAgent (£19/month) is gold standard for CIS, QuickBooks (£6/month) is budget option, Xero (£14/month) is middle ground
• Sign up for MTD by early March 2026 to avoid postal delays
• CIS deductions must be claimed in quarterly submissions or you'll overpay tax
• MTD doesn't replace Self-Assessment — you still file a final return by 31 January
• Late quarterly submissions = £200-£800/year in penalties

6 April 2026 is 6 weeks away. If you haven't started, start today.