See It In Action
Your entire practice. One screen.
Real screenshots from a live SIMA practice. No mockups. No Photoshop. This is what your firm looks like inside SIMA.
Manage clients, invoices, tax filings, and your entire practice from one AI-powered platform. HMRC MTD compliant from day one.
Every firm is different. That's why SIMA adapts to where you are today and grows with you tomorrow.
Your problem: You're spending evenings on admin instead of growing your client base. Spreadsheets, manual VAT returns, and HMRC deadlines are eating your time.
SIMA gives you:
Automated MTD filing, client portal, invoicing, and document management. Everything a solo practice needs from £49/month. You get your evenings back.
Start Free Trial →Your problem: You've got 5-50 clients and a small team, but no system tying it together. Client info is scattered, deadlines get missed, and you can't see firm-wide profitability.
SIMA gives you:
AI-powered practice management with team messaging, HMRC MTD for all taxes, client risk scoring, and real-time dashboards. Run your firm like a firm, not a freelance gig.
Start Free Trial →Your problem: Multiple offices, multiple teams, no single view. You need white-label capability, API access, and enterprise-grade security without enterprise-grade pricing.
SIMA gives you:
Everything in Professional plus white-label branding, multi-office management, custom integrations, dedicated account manager, and SLA guarantee. Your brand, our engine.
Subscribe Enterprise →Real screenshots from a live SIMA practice. No mockups. No Photoshop. This is what your firm looks like inside SIMA.
Stop juggling spreadsheets, email, and disconnected tools. SIMA brings everything into one intelligent workspace.
Real-time overview of your firm. Revenue, outstanding invoices, client health scores, and team activity — all in one view.
Full client profiles with documents, notes, communication history, risk scores, and engagement tracking. Everything in context.
Generate professional invoices in seconds. AI pre-fills line items based on engagement history. Online payments via Stripe.
AIVAT returns, Self Assessment, ITSA, and Corporation Tax — file directly to HMRC from inside SIMA. No third-party bridge needed.
AI-powered monitoring that watches your practice 24/7. Anomaly detection, deadline alerts, compliance warnings, and risk scoring.
AITeams-style messaging with clients and team members. File sharing, read receipts, presence indicators, and threaded conversations.
Centralised document storage with smart categorisation. Upload receipts, scan with AI, and auto-attach to the right client.
GAAP-compliant financial analysis, trial balance validation, and AI-generated management reports. Your junior accountant that never sleeps.
AIGive clients their own secure portal. They upload documents, view invoices, message your team, and track progress — beautifully.
SIMA wasn't built in a Silicon Valley lab. It was built inside a real accounting practice — SIMA Global Advisory — to solve the problems we faced every day. When other firms started asking for it, we turned it into a product.
Every feature exists because a real accountant needed it. Every workflow was tested with real clients. That's the difference between software built by engineers guessing what accountants need, and software built by accountants who code.
"We built SIMA because every tool we tried was either too complex, too expensive, or designed by people who'd never filed a tax return. This is the platform we wished existed."
No hidden fees. No per-client charges. Cancel anytime.
Perfect for sole practitioners getting started with modern practice management.
For established practices ready to scale with AI-powered intelligence.
For larger firms needing white-label, multi-office, and dedicated support.
| Feature | SIMA | Sage | Xero PM | TaxCalc |
|---|---|---|---|---|
| HMRC MTD Filing (Direct) | ✓ | Bridge needed | Limited | ✓ |
| AI-Powered Features | ✓ Built-in | Add-on | Limited | ✗ |
| Client Portal | ✓ Included | Extra cost | Basic | ✗ |
| Team Messaging | ✓ Built-in | ✗ | ✗ | ✗ |
| All-in-One Platform | ✓ | Multiple products | Multiple products | Tax only |
| Starting Price | £49/mo | £60/mo+ | £55/mo+ | £42/mo+ |
Yes. We help every new firm migrate their client data, documents, and records into SIMA. Most migrations take less than a week. We handle the heavy lifting so you don't lose a single day of productivity.
Absolutely. SIMA uses bank-grade encryption (AES-256), is hosted on enterprise infrastructure with 99.9% uptime, and is fully GDPR compliant. Your client data is encrypted at rest and in transit. We never share your data with third parties.
Your chosen plan starts billing automatically after 14 days. You can cancel anytime before the trial ends and you won't be charged. No lock-in contracts, no cancellation fees. If you need more time to evaluate, just ask.
Yes. SIMA connects directly to HMRC's Making Tax Digital APIs. VAT returns, Self Assessment (ITSA), and Corporation Tax can all be filed from inside the platform. No bridging software needed. No CSV exports. One click, filed.
Starter includes up to 50 clients. Professional and Enterprise plans include unlimited clients with no per-client fees. Whether you have 10 clients or 1,000, you pay the same monthly price.
Yes. Every plan includes a secure client portal where your clients can upload documents, view invoices, message your team, and track progress. It's branded to your firm, not SIMA. Your clients see your name, not ours.
Professional and Enterprise plans include AI invoice drafting (generates invoices from engagement history), AI client risk scoring (flags at-risk clients before problems arise), AI financial analysis and validation, and SIMA Guardian (24/7 monitoring with anomaly detection and deadline alerts). The AI works alongside you, not instead of you.
SIMA was built inside SIMA Global Advisory, a real UK accounting practice. It's not a Silicon Valley product designed by engineers who've never filed a tax return. Every feature exists because a practising accountant needed it. SIMA Technologies Ltd is the product company, part of AIONIQS.
14-day free trial. Cancel anytime. Set up in under 5 minutes.