HMRC Registered Agent
CIS Specialists
Stop Worrying About Compliance. Start Growing Your Business. We fix what others miss—your comprehensive partner for SMEs, construction pros, and freelancers across England & Wales. MTD ITSA is NOW LIVE for 2026: Self-employed & landlords over £50k, avoid penalties—get compliant fast.
In 30 minutes, we'll uncover 3+ hidden savings, start to fix compliance risks, and map your growth—guaranteed.
Limited Only 3 Free Sessions Left This Month—Secure Yours Before MTD Fines Mount
Typical response within 24 hours
We specialise in businesses like yours
Your strategic financial partner, not just your accountant
Imagine ditching financial dread for daily confidence...
See your business soar with proactive insights at your fingertips...
Feel the freedom of a partner who handles the heavy lifting...
Xero Gold Partner. Expert cloud accounting setup and support.
From refunds to verifications, we handle it all—feel the relief of compliance without the admin grind.
We catch issues early, turning potential crises into quick wins—so you never face surprises.
Typical client onboarding in just 1 week. Get sorted quickly and stress-free.
Navigate 2026 rules seamlessly; avoid live penalties and quarterly stress.
We know your name, your goals, and your industry inside out, making every interaction feel personal and powerful.
We hunt down every deduction others overlook, legally slashing your bill so you see real growth in your bank.
Certified Public Accountants Association member. Qualified professionals you can trust.
Experience the difference that genuine care makes
Offshore delays and generic advice
Once-a-year check-ins
Hidden fees and one-size-fits-all
UK-based experts who know your world
Always-on proactive partnership
Transparent, tailored strategies that save real money
We manage CIS for 50+ construction businesses—from £40k to £8M revenue—recovering £1000's in average refunds per client.
Sound familiar?
Here's how we fix it:
Self-employed & landlords over £50k: Quarterly submissions are mandatory. Late filings mean automatic HMRC fines—up to £400+ per quarter. Get compliant before it's too late.
Download Free MTD Compliance Checklist6 Steps to Penalty-Proof Your Business
Book Your Free 30-Min Strategy SessionIn 30 minutes, we'll pinpoint 3+ ways to save money, ensure 2026 compliance, and fuel growth—guaranteed results or walk away wiser.
See what our clients say about working with Fortis
"Caroline & William have been nothing but amazing from the get go! The confidence I've found with their backing alone has been life changing."
"These guys saved my business! After spending 2 years with a different accountant, I decided to switch and it's the best decision I ever made."
"William & Caroline are so efficient, effective & made my whole experience of tax returns so simple. Saving me THOUSANDS of pounds!"
Download free guides to help manage your finances better
Essential steps to get ready for Making Tax Digital compliance.
Download Free Guide NowStrategies to predict, monitor, and improve your business cash flow.
Download Free Guide NowAll under one roof - comprehensive financial support for your business
Book your free 30-minute strategy session and discover how we can help your business thrive.
Limited Only 3 Free Sessions Left This Month—Secure Yours Before MTD Fines Mount
Based in Daventry
Serving England & Wales
Remote Services Available
In 30 minutes, we'll pinpoint 3+ ways to save money, ensure 2026 compliance, and fuel growth—guaranteed results or walk away wiser.