Tax Codes Explained
Understand what a tax code is, where to find it and why your tax code affects how much Income Tax is deducted through PAYE.
View Tax Code Guide →
HMRC Tax Guidance
Clear Guides to HMRC & UK Tax
Understand common HMRC topics including tax codes, emergency tax, P45s, P60s, P800 calculations, overpaid tax, refunds and the documents used to manage your UK tax position.
Popular HMRC topics
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Tax codes and emergency tax
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P45s, P60s and PAYE records
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P800s and overpaid tax
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Tax refunds and HMRC correspondence
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Straightforward tax code explanations
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Guides to common HMRC documents
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Tax overpayment and refund guidance
Understand HMRC
Understand the information HMRC uses to manage your tax
Tax codes, PAYE documents and HMRC calculations can be difficult to understand when you do not deal with them every day. These guides explain common HMRC terminology and documents, why they matter and what you may need to check if something does not look right.
Looking for guidance based on how you work? Visit our PAYE Tax Hub, Self-Employed Tax Hub or CIS Tax Hub.
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Tax Codes, Refunds & HMRC Guides
Start with the HMRC topic you need help understanding.
Emergency Tax Codes
Learn why an emergency tax code may be used after starting or changing a job and what to check if too much tax appears to have been deducted.
View Emergency Tax Guide →BR Tax Code
Understand what the BR tax code generally means and why it can appear when you have another job, pension or source of PAYE income.
View BR Tax Code Guide →1257L Tax Code
Guidance to understanding one of the commonly seen PAYE tax codes and why an individual's actual code can differ.
View 1257L Guide →P800 Tax Refunds
Understand what an HMRC P800 tax calculation is and what it can mean if HMRC says you have paid too much or too little tax.
View P800 Guide →Overpaid Tax
Explore common reasons tax may be overpaid and what information can help when reviewing your tax position.
View Overpaid Tax Guide →How to Claim a Tax Refund
Understand common routes for correcting overpaid tax or claiming eligible tax relief and the information that may be required.
View Tax Refund Guide →HMRC Mileage Rules
Explore HMRC guidance around qualifying business journeys, mileage reimbursement and employee mileage tax relief.
View Mileage Guide →
HMRC & PAYE documents
Understand Your Tax Documents
Learn what common PAYE and HMRC documents are used for and why they can be important when checking your tax position.
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P45 Explained
Understand the information shown on a P45 when you leave employment and why a new employer may need it.
P60 Explained
Understand the annual PAYE information shown on a P60 and how it can help when checking income and tax deducted.
P800 Explained
Learn what HMRC's P800 calculation is and why you may receive one after a review of your PAYE tax.
Tax Code Notices
Understand why HMRC may change a tax code and what information to review when you receive a coding notice.
Find your starting point
Not sure which HMRC guide you need?
Choose the situation that most closely matches what you are trying to understand.
My tax code looks wrong
Start with our Tax Codes Explained Guide .
I have just changed jobs
Read about Emergency Tax Codes and P45s.
HMRC says I have overpaid tax
Start with our P800 Tax Refund Guide .
I think too much tax has been deducted
Read our Overpaid Tax Guide or use our tax refund calculator.
Tax Refund Support
Think you may have paid too much tax?
Go Tax Refunds can review your circumstances and help you understand whether you may have overpaid tax or be eligible for tax relief on qualifying work-related expenses.
Get in touch
Need help getting started?
Get in touch with our team or book a call for clear, straightforward support with your tax refund or return.
