What does the tax code
1000L mean?

Let us deal with the money question first, because it is the reason most people are here and the answer is short.

1000L was the standard UK tax code for the 2014/15 tax year, giving £10,000 of tax-free pay. The window for claiming anything relating to 2014/15 closed on 5 April 2019. If you overpaid tax that year, for any reason, it is not recoverable now. No process reopens it, and anyone suggesting otherwise is not describing how the time limits work.

That is not a satisfying answer, so the rest of this page is about what is actually still useful.

Why this code is remembered when others are not

£10,000 was a milestone. Successive governments had spent years raising the Personal Allowance towards a round £10,000, and 2014/15 was the year it arrived. The resulting code, 1000L, is the tidiest number the system has ever produced, and tidy numbers stick.

That is genuinely most of the explanation for the search volume. Compare it with 1060L for 2015/16, which almost nobody remembers, despite being the very next year.

The rest of the explanation is that 2014/15 sits at the edge of the period covered by the records people still own. Boxes of paperwork from that era are exactly the ones being cleared out now.

The four year rule, stated plainly

The general time limit for a tax claim is four years from the end of the tax year concerned. Applied to the codes in this family:

Every row above 2022/23 is closed. There is no discretion, no appeal to fairness, and no special case for someone who only just discovered the problem. The deadline is the deadline.

It is worth being clear about what "closed" means, because it is stronger than it sounds. It is not that a claim becomes difficult, or that HMRC is unlikely to agree, or that you would need a good reason. The claim simply cannot be made. HMRC has no power to accept it and no discretion to make an exception, so there is nothing to negotiate and nobody to appeal to. Understanding that saves a great deal of wasted effort, and it is also why any service offering to recover tax from a decade ago should be treated with considerable suspicion.

What old records are still good for

None of this makes 2014/15 paperwork worthless. It just means its value is not a refund.

Evidence of a long running error. If a benefit was sitting in your code in 2014/15 and is still there now, the old document establishes how long it has been running. That does not reopen closed years, but it makes a claim for the open ones considerably easier to argue.

Employment history. Old P60s and P45s are a record of who you worked for and when. Useful for pension tracing, for state pension record queries, and for reconstructing a career when nobody else has kept the details.

National Insurance record checks. Gaps in your NI record affect your state pension, and the rules for filling gaps are separate from the four year income tax limit. If you are checking your record, old P60s are the evidence of what should be there.

Mortgage and immigration applications. Both routinely ask for historic income evidence going back further than four years.

Probate and estate work. Historic records are frequently needed when settling someone's affairs.

So keep them if you have them, but stop hoping they contain money.

The asymmetry nobody mentions

There is an uncomfortable point buried in all this, and it is better heard from us than discovered later.

Your window for claiming money back is four years. HMRC's window for coming after money you underpaid is not the same length in every situation. The ordinary assessment period is also four years, but it extends where an underpayment resulted from carelessness, and extends a great deal further where it resulted from a deliberate act.

The practical consequence for an ordinary employee is limited, because a wrong tax code is not something you did. If HMRC coded a benefit incorrectly, that is not your carelessness, and the ordinary limit applies. But it is worth knowing that "the year is closed" is a statement about your claim, not a general statement that nothing from that year can ever be revisited.

Two things follow.

Do not throw away records to make a point. The paperwork that proves you were overpaying is the same paperwork that proves you were not underpaying.

Do not assume silence means agreement. A year passing without a letter is not confirmation that the year was right. It usually just means nothing in HMRC's records flagged a discrepancy, which is exactly the situation in which an error can survive undisturbed for a decade.

The balance of risk for most people still points the same way: the money that goes unclaimed vastly exceeds the money HMRC later reclaims. But the two clocks are not mirror images of each other, and it is worth knowing that before deciding what to keep.

The thing actually worth doing today

If discovering an old code has made you suspicious about your tax, the productive move is to look forward from 2022/23 rather than backwards from 2014/15.

Four years are currently open: 2022/23, 2023/24, 2024/25 and 2025/26, plus the current year. The oldest of them closes on 5 April 2027, and after that it goes the way of every row in the table above.

Coding errors persist. A benefit that ended and was never removed, a relief never claimed, an interest estimate that stopped matching reality, an old employment still showing as live. If any of those affected you in 2014/15 and nobody fixed it, the chances are good that it was still doing so in the years you can still claim for.

Start with your current code, because a problem that exists today almost certainly existed last year. Our guide to checking your tax code shows the five places to find it, and our free tax code checker will estimate what it should be for each open year. It gives an estimate rather than advice.

Then, for the closed-but-claimable years, our guide to reclaiming overpaid tax covers how to claim, what evidence helps, and why waiting for HMRC to notice is not a plan.

People also ask

What does tax code 1000L mean?

Can I claim a tax refund for 2014/15?

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Is there any point keeping paperwork from 2014/15?

Why do people still search for the 1000L tax code?

Related tax codes: 1100L tax code | 1150L tax code | 1250L tax code | 1257L tax code | L tax code

HMRC: What your tax code means