HMRC rejected my sign-in details but they are correct

Short version. You are probably right that your details are correct, and HMRC is also right to refuse them. HMRC sends one identical error for five different problems, and only one of them is a wrong password. The usual cause is that your Government Gateway user ID, your password and your company’s Unique Taxpayer Reference (UTR) are each correct on their own but do not all belong to the same HMRC account. Signing in to HMRC and looking at what that account actually contains takes about two minutes and tells you which of the five it is.

Nothing was filed when this happened. Your return was not submitted to HMRC, and you will not be charged again to resubmit once it is sorted.

Why one error means five different things

When HMRC refuses a Corporation Tax submission it returns “Authentication Failure. The supplied user credentials failed validation for the requested service”. That single message covers all of these:

• The Government Gateway user ID or password genuinely has a typo.
• The user ID and password are right, but that account has never had Corporation Tax added to it.
• Corporation Tax was added, but the enrolment was never activated because the code HMRC posted out was not entered.
• The account is enrolled and activated, but for a different company than the UTR you are entering.
• You are signing in to a personal tax account rather than the business one. Plenty of people have both, with different user IDs.

Because the message is the same in all five cases, checking your password again cannot tell you anything. You have to look at the account.

Check which account you are actually signed into

Go to gov.uk/log-in-register-hmrc-online-services and sign in with the same user ID and password you gave us. Two things to note once you are in:

• The user ID you signed in with. This is what has to match the Government Gateway user ID in your filing. It is usually 12 digits.
• Whether this is the business account. If you see Self Assessment or your own personal tax and no Corporation Tax at all, you are in a personal account. The company’s Corporation Tax will be on a different user ID.

If you cannot sign in at all, the problem really is the user ID or password, and you can recover either from that same page.

Check the UTR is added to that account, and activated

Still signed in, look for Corporation Tax in the list of services on the account. Three separate things have to be true:

• Corporation Tax is listed. If it is not there, this account is not enrolled for it and cannot file, however correct the password is.
• The UTR shown matches the UTR you are entering. HMRC displays the 10-digit UTR the account is enrolled for. If it shows a different number, you are filing for one company with another company’s account.
• It is active, not awaiting activation. If HMRC is still waiting for the activation code it posted to your registered office, the enrolment does not work yet. The code expires after 28 days and you can request a new one.

Our guide to setting up a Government Gateway account for Corporation Tax covers adding Corporation Tax and the activation code step by step, including what to do if your code has expired.

All three have to match on the same account

This is the part that catches most people. It is not enough for each detail to be correct somewhere. To file, all of the following must be true at once:

• the Government Gateway user ID and password sign in to one particular account,
• that account has Corporation Tax added and activated,
• and the UTR that account is enrolled for is the UTR of the company you are filing for.

If you run more than one company, the most common version of this is using the Government Gateway ID for company A while filing for company B. HMRC recommends a separate Government Gateway ID for each company, so check you are using the right one for this filing.

If the UTR is missing, or is not your company’s

There are three versions of this, and they need different fixes.

• Corporation Tax is not listed on the account. Add it, then enter the activation code HMRC posts to your registered office. Allow about ten working days for the post, so do not leave this until your deadline.
• A different company’s UTR is shown. You are in the wrong account for this filing. Sign in with the Government Gateway ID enrolled for the company you are filing for, or set one up for it.
• You do not know the company’s UTR, or think it is wrong. It is the 10-digit number HMRC posted to your registered office after incorporation, and it appears on HMRC Corporation Tax letters such as the “Notice to deliver a Company Tax Return”. It is not your personal UTR and it is not the Companies House registration number.

If the UTR should be on the account and is not, or HMRC has it against the wrong company, only HMRC can put that right. Call the HMRC Online Services Helpdesk on 0300 200 3600. They can sometimes link a UTR to an account faster than the postal activation route, which matters if your deadline is close.

If it still fails

If Corporation Tax is listed against the right UTR, it is active, and the submission is still refused, contact us and tell us:

• the Government Gateway user ID you are using,
• the UTR shown against Corporation Tax in that account,
• and that the enrolment shows as active rather than awaiting activation.

Never send us your Government Gateway password. We do not need it to investigate, we will never ask for it, and you should not share it with anyone. When you file, your password is used once to send that submission to HMRC and is never stored.

You can also see the exact response HMRC gave on your filing page, along with what each HMRC error code means.

This article is general guidance, not tax advice. If HMRC’s records for your company look wrong, HMRC is the only party that can correct them.