Changed Jobs? What to Do With Your Old 401(k) or Workplace Pension (US & UK Guide)

Every job change leaves a financial trail behind it — and for young professionals, who switch employers every few years, that trail is a scattered set of retirement accounts. In the US, it is an old 401(k) sitting with a former employer's plan. In the UK, it is a string of small workplace pension pots: an estimated £31 billion of UK pension money sits unclaimed in lost or forgotten pots. Ignoring them is the default, but it is rarely the best choice. Old accounts can carry higher fees, sit in default funds that no longer suit you, and — worst of all — get forgotten entirely. Here is what to do with old retirement accounts after a job change, with the country-specific rules that decide whether you should move the money or leave it alone.

Step zero: find everything you left behind

Before deciding anything, make a list. One line per pot: provider, account or policy number, current value, and annual charges.

• US: contact your former employer's HR or benefits team, and the plan administrator named on old statements. If the company no longer exists, the US Department of Labor's Employee Benefits Security Administration can help track down abandoned plans.
• UK: use the free GOV.UK Pension Tracing Service (online, or 0800 731 0193) — give it an employer name and it returns the scheme's contact details. It finds the provider, not your balance; you then ask each scheme for a current value and its charges in writing. Check old payslips and annual statements too.

Write the list somewhere your family can find it. Unclaimed retirement money is a real and growing problem in both countries, and the fix is literally a piece of paper.

US: your four options for an old 401(k)

When you leave an employer, the 401(k) you built there does not follow you automatically. You have four choices:

• Leave it with the old employer. The money stays invested in the same plan. This is fine if the plan has low fees and good funds — but you can no longer contribute, and old employers are allowed to force out very small balances, so tiny pots do not sit still forever.
• Roll it into your new employer's plan. If the new plan accepts rollovers in and has decent fees, this keeps everything in one place and preserves the age-55 rule (below). Ask the new plan administrator for their rollover instructions before you start.
• Roll it into an IRA. Pre-tax 401(k) money goes into a traditional IRA with no tax bill; Roth 401(k) money goes into a Roth IRA. (Converting pre-tax money into a Roth IRA means paying income tax on the converted amount now.) IRAs usually offer wider investment choice and lower fees than employer plans.
• Cash it out. This is almost always the wrong answer — see the math below.

US: the rollover mechanics that decide your tax bill

HOW you move the money matters as much as WHERE. There are two paths, and the wrong one has a trap built in:

• Direct rollover (trustee-to-trustee). The old plan sends the money straight to the new account — sometimes as a check made payable to the new custodian "for the benefit of" you, not to you personally. Nothing is withheld and there is no deadline pressure. This is the move you want. Ask for it by name.
• Indirect rollover (the 20% trap). The plan cuts a check to YOU. By law it must withhold 20% for federal taxes first. You then have 60 calendar days to deposit the FULL original amount into a new retirement account — which means replacing that withheld 20% from your own pocket. Deposit only what you received and the shortfall is treated as a taxable distribution: income tax on it, plus a 10% early-withdrawal penalty if you are under 59½. You get the withheld amount back as a credit when you file — months later.

Real numbers: a $60,000 old 401(k) taken as an indirect rollover means a $48,000 check in your hand. To complete the rollover tax-free you must deposit $60,000 within 60 days — finding $12,000 from savings. Deposit only the $48,000 and the missing $12,000 is taxed as income, plus roughly $1,200 in early-withdrawal penalty. (The "one rollover per 12 months" limit, by the way, applies to IRA-to-IRA indirect rollovers — not to 401(k)-to-IRA moves. Yet another reason to use direct rollovers.)

Two warnings before you move anything. The age-55 rule: if you separated from your employer at 55 or older, you can take penalty-free withdrawals from that employer's plan; rolling the money into an IRA destroys that privilege, so check your situation before consolidating. And the true cost of cashing out: a $60,000 balance cashed out in the 22% federal bracket costs about $13,200 in tax plus a $6,000 penalty before any state tax — but the forfeited growth is the bigger wound. Left invested at a hypothetical 7% a year, that $60,000 becomes well over $400,000 in 30 years.

UK: your options for old workplace pensions

Nothing happens automatically when you change jobs — your pot stays where it is, invested in the same funds. You have three choices:

• Leave it where it is. A perfectly good default for older pots with valuable guarantees (more below). The money keeps growing; you just cannot add to it.
• Transfer it into your new employer's scheme, if the new scheme accepts transfers in. One login, one set of paperwork.
• Move it into a personal pension or SIPP. More investment choice and often lower charges, at the cost of managing it yourself.

One thing NOT to wait passively for: the Pension Schemes Act 2026 created the legal framework for automatic consolidation of small dormant pots into consolidator schemes — but it is not switched on yet, and no start date has been published. For pots of a few hundred pounds, waiting for the automatic route costs you nothing. For larger pots, decide now.

UK: the five checks to run before you move a pot

Consolidating UK pensions is easy to do and sometimes expensive to undo. Run these checks first:

• Exit fees. Older policies can charge to leave. Get the number in writing — it is the single figure that matters most on a small pot.
• Safeguarded benefits. Some older schemes carry guaranteed annuity rates, a protected pension age, or with-profits guarantees. A transfer can destroy these permanently, and on a large pot they can be the whole value.
• Protected tax-free cash. Pre-2006 pensions can carry enhanced tax-free cash above the standard 25% — moving the pot forfeits it.
• The £30,000 advice rule. If a defined-benefit (final-salary) pension is worth more than £30,000, you are legally required to take regulated financial advice before transferring. The regulator's position is that most people with DB pensions are better off keeping them — and unfunded public-sector pensions (NHS, teachers, civil service, armed forces) generally cannot be transferred at all.
• Compare the destination honestly. A transfer only helps if the receiving scheme is actually cheaper or better. Typical defined-contribution transfers take 4 to 8 weeks; defined-benefit transfers can take 3 to 6 months.

Also: never pay a percentage to a company that offers to "find and combine" your pensions for you. The tracing service is free, and consolidation — manual or the coming automatic kind — does not need a middleman taking a cut.

5 mistakes that quietly shrink your retirement money

1. Cashing out when you change jobs. The $60,000-to-$400,000 math above is the most expensive financial decision many young professionals ever make — and it is made in an afternoon.
2. Doing an indirect rollover by accident. A check made out to you instead of your new custodian triggers the 20% withholding and the 60-day clock. Always request a direct rollover.
3. Moving a pot with guarantees you never checked. Guaranteed annuity rates and protected tax-free cash are irreplaceable once surrendered. Ask the old provider what you would lose — in writing.
4. Consolidating a final-salary pension without advice. Exchanging guaranteed lifetime income for a cash value you invest yourself is irreversible, and the law requires advice over £30,000 for a reason.
5. Having no list at all. Every forgotten pot is a pot that cannot be claimed, rebalanced, or nominated to the right beneficiary. Trace them, value them, write them down.

The bottom line

Job changes scatter retirement money; your job is to gather it deliberately. In the US, that means choosing between the old plan, the new plan, and an IRA — and executing the move as a direct rollover so the 20% withholding and the 60-day rule never touch you. In the UK, it means tracing every pot for free, checking for guarantees before you consolidate, and knowing which transfers the law treats as serious enough to require advice. None of this takes more than a few hours spread over a month, and it compounds for decades. Everything here is educational — retirement accounts carry tax rules with real deadlines, so confirm the specifics of your plans with a qualified professional before you move any money.