Your clients'
deadlines. Covered,
30 days early.
Email alerts 30, 14, 7 days and morning-of — every UK filing regime, every client, one inbox. No dashboard to check.
- ✓You manage UK companies for clients
- ✓You want deadlines in your inbox
- ✓ICAEW / ACCA / AAT / ICB regulated
- ✗You need HMRC portal integration
- ✗You only manage your own company
- ✗You need non-UK compliance
or start with free plan (5 clients, no card needed)
See it in action — check any company free.
Type a company name or number to see its next Companies House deadlines instantly. No signup needed.
The alert that lands in your inbox.
Plain email. No app to open. No dashboard to remember to check.
Preventable filing penalties hit UK businesses in their millions every year.
These are your clients' filings. The accountant is usually the first call when something goes wrong.
HMRC penalties issued across all taxes in 2024–25, up from 8 million the year before
HMRC Annual Report, 2024–25In scope for MTD ITSA from April 2026 — four quarterly updates plus a year-end declaration
GOV.UK policy paperMissed deadlines are among the errors that most often drive PI claims against accountants. Howden, the PI insurer for accountants, lists missed deadlines among the common clerical errors behind claims — this is liability exposure, not just client annoyance. Howden, 2026 →
Four alerts per deadline. Nothing slips through.
30, 14, 7 days, and the morning it's due — so nothing creeps up on you.
A full month's notice. Start gathering what you need — there's time to do this without pressure.
The midpoint checkpoint. Confirm everything's in order and nothing's slipped through.
Everything you need to file is in the email. This is when most people act.
The morning-of safety net. If you haven't filed yet, today is the day.
Alerts at 09:00 (Starter) or 07:00 (Pro). RTI payroll follows a 7/3/0-day schedule.
The alerts you need.
None of the overhead.
Practice tools and spreadsheets only flag what's been keyed into them, behind a login. PenaltyProof watches your whole filing calendar and emails you ahead of every deadline — alongside whatever you already run.
Companies House already sends free reminders. Here's how PenaltyProof differs. CH's free service covers two filings — your accounts and confirmation statement — with a reminder a few weeks before each. PenaltyProof covers the whole calendar: Companies House, VAT, PAYE, Corporation Tax, Self Assessment and more, in one morning email.
Blue ticks mean partial or varies by tool — some practice software sends reminders too, but only for what's been entered into it.
Every obligation covered. Zero client data needed.
Public Companies House data only — nothing from HMRC, your accounting software, or client financials. Built for ICAEW, ACCA, AAT and ICB members.
10 UK filing regimes
CH, Corporation Tax, VAT, RTI, P11D, Self Assessment, MTD ITSA, pension, charity and ECCTA — every obligation your clients carry.
Alerts land at 07:00
Priority delivery on Pro; 09:00 on Starter. No cron drift, no missed mornings.
Live in ~2 minutes
Add a Companies House number. We resolve the name, detect filing history, and start monitoring immediately.
No client data — ever
Public Companies House data only. No accounting software access, no HMRC data, no client financials. Nothing your clients haven't already made public.
Works in any inbox
Alerts arrive as plain emails. Gmail, Outlook, Apple Mail — no app to install, no dashboard to check.
Official data, every day
We poll the official Companies House API daily — the same data on the CH website, checked automatically for every client.
Built for the way you actually work
Email alerts that fit your existing workflow. No new software to learn, no portal to check, no client data required.
Alerts arrive at 07:00 (Pro) or 09:00 (Starter) directly in your inbox. Gmail, Outlook, Apple Mail — whatever you already use. No portal to log into, no feed to remember to check.
All deadlines come from the official Companies House API, checked daily. We don't connect to HMRC, access your accounting software, or handle any client financials. No sensitive data. No integration risk.
Add clients individually, paste a list of company numbers, or upload a CSV. All clients appear in a single account. Alerts go to one inbox — yours, or a shared practice address.
Built because accountants kept asking for it.
Three problems came up again and again when we spoke to accountants — they're the reason PenaltyProof exists.
Spreadsheets don't know when Companies House changes a date.
A client's confirmation statement date shifts, the accountant's calendar doesn't update, and the first sign anything's wrong is a penalty notice. The information was always public — nothing was watching for the change.
The gap between tools is where deadlines fall through.
Separate systems for CH, HMRC, payroll, and pension each alert in isolation. No single view covers everything. Missed deadlines happen in the handoff between tools — not from carelessness.
A reminder you have to go looking for isn't really a reminder.
Companies House's free reminders cover two filings, and a dashboard only helps if you remember to open it. What accountants keep asking for is one advance warning, across every regime, that just lands in their inbox.
PenaltyProof is the answer to all three — built specifically because nothing else was.
Alerts running by tomorrow morning.
Takes about 2 minutes. Works with Gmail, Outlook, or any email client.
The Penalty-Proof Promise
If a client on your active paid plan receives a penalty for a deadline we failed to alert you about, we credit your account the full amount — up to 12 months of subscription fees. No quibble.
Active paid plans only. Company must be added at least 35 days before the filing deadline. Credit applied to account balance; not redeemable as cash. Submit within 30 days of the penalty notice date with a copy attached. Full eligibility terms →
Questions? Email hello@penaltyproof.co.uk
Simple, transparent pricing
No contracts. Cancel any time. Annual billing saves ~17%.
- 5 companies monitored
- Companies House & ECCTA alerts
- 30/14/7-day advance warnings
- Overdue-day alerts
- No card required
- VAT, CT, payroll, SA, MTD ITSA alerts
- Pension auto-enrolment alerts
- Priority 07:00 delivery
- Up to 50 companies
- 9 UK filing regimes (CH, VAT, CT, RTI, P11D, SA, MTD ITSA, Charity, ECCTA)
- 30/14/7-day + due-date alerts
- 09:00 morning delivery
- Monthly digest
- 30-day free trial included
- Pension auto-enrolment alerts
- Priority 07:00 delivery
- Second alert recipient
- Unlimited companies
- All 10 UK filing regimes
- Pension auto-enrolment alerts
- 30/14/7-day + due-date alerts
- Priority 07:00 delivery
- Second alert recipient
- Weekly digest
- 30-day free trial included
- 3 seats included
- Unlimited companies
- All 10 UK filing regimes
- Pension auto-enrolment alerts
- Priority 07:00 delivery
- Team logins + audit trail (at launch)
- White-label client alerts (at launch)
- Dedicated onboarding call
Questions? Email hello@penaltyproof.co.uk · Already a customer? Send me a manage link →
We store your email address and the company numbers you choose to monitor. No client financial data, no HMRC access, no accounting software integration. Privacy policy · Terms
Common questions
Everything accountants typically ask before signing up.
Stop tracking deadlines
manually. Start getting alerts.
Companies House issued 317,985 penalties to UK businesses last year —
most for filing late, all with advance notice possible.
No credit card for free plan · Cancel paid plan any time during trial