Back to Community
1

Can't find last year's submitted CT600 from HMRC online service

Posted by Carole Cheung 31 Jan 2026 at 12:35
I used an external software company to file CT600 to HMRC last Feb, and received HMRC's email confirmation subsequently. However, I am unable to find that filing record in Feb 2025 when I logged on to HMRC online services, as I was trying to download my previous filings before end of March. So far, I didn't receive any letter from HMRC for late filing.

How can I ensure that HMRC already received the CT600 submitted in Feb last year?

3 Comments

T
Tim Fouracre Staff 31 Jan 2026 at 14:05
Thanks for getting in touch. From your message, it sounds like your CT600 for February 2025 was submitted through a different software provider, not TinyTax (your account was created yesterday).

To verify HMRC received your CT600:

1. Check with the software provider you used - They should have a record of the submission and the HMRC acknowledgement (IRmark/correlation ID)

2. Contact HMRC directly on 0300 200 3410 (Corporation Tax helpline) - They can confirm whether a CT600 was received for your company. Have your UTR and company details ready.

3. Check your HMRC Business Tax Account - Sometimes filings don't appear immediately in the online portal but are still processed. The absence of a late filing penalty notice is a good sign.

4. Find your original HMRC confirmation email - This contains the submission receipt which proves HMRC received the filing.

If you'd like help filing your next CT600 through TinyTax, we'd be happy to assist - just start a new filing from your dashboard.
C
Carole Cheung 31 Jan 2026 at 15:30
Thanks, Tim, for your promptness. Although I couldn't find last Feb's submitted returns from HMRC online service, I have on hand the acknowlwdgement from HMRC, and only from the software company's submission report, the IRmark/correlation ID references.
Should I proceed to file for this year's return through TinyTax now? Or, should I reconfirm with HMRC first before doing so?
T
Tim Fouracre Staff 31 Jan 2026 at 16:07
Great news - if you have the HMRC acknowledgement email, that's your definitive proof the CT600 was received. The IRmark is HMRC's digital receipt confirming they processed the submission. No need to reconfirm with them before proceeding.

Returns filed through third-party software can take a while to appear in HMRC's online portal - it should show up eventually, but there can be delays.

You're safe to proceed with this year's filing through TinyTax whenever you're ready. Just head to your dashboard and start a new filing for your company.