Buckets are a psychological device that happens to work

This is written to be used rather than admired. Each section below is a decision about bucketing a retirement portfolio, and each one has a default.

The economics are neutral

Three buckets holding cash, bonds and equities are the same portfolio as one account holding the same proportions. No additional return is created by the labelling, and anyone claiming otherwise is describing a feeling. This is sometimes offered as a criticism, and it misses what the structure is for.

The benefit is behavioural, which is not the same as imaginary.

Why the labelling helps

Seeing that the next few years of spending sits in cash removes the sense that a market fall threatens this month. That directly addresses the anxiety that causes forced selling, which is a genuine financial risk. It also makes the long-horizon money feel long-horizon, which makes it easier to leave alone.

The useful part is this: mental accounting is being used deliberately here rather than being allowed to operate by accident.

The refill rule is the hard part

Bucketing only works if there is a stated rule for moving money from the growth bucket to the cash bucket. Common approaches refill after good years, or at scheduled intervals unless markets have fallen substantially. Without a rule, the cash bucket drains and never refills, and the structure quietly stops protecting anything.

The useful part is this: this is the clause most often missing from otherwise well-constructed plans.

Sizing the near-term bucket

Commonly one to three years of spending net of any guaranteed income, though the right size depends on your circumstances. A larger buffer costs more in expected return; a smaller one exposes you to selling during a decline. The trade-off is real and neither end of it is obviously correct.

Anyone quoting a single correct number is describing a preference rather than a finding.

Keep the total allocation in view

A risk of bucketing is losing sight of the overall allocation, since attention moves to the individual pots. The combined proportions still determine your actual risk and should be checked at the annual review. Rebalancing across buckets is how the total is maintained, and it is often what the refill rule is doing.

Thinking in pots and checking in totals is the workable combination.

Some of this will suit you and some will not, and that is the point.

Practical caveats

Multiple accounts can mean multiple sets of charges, so the structure should not be built at unnecessary cost. Tax treatment of different account types varies substantially by country and can make some arrangements far better than others. The buckets can also be notional within one account, which achieves the psychological effect without extra fees.

How to structure this for your own situation is a matter for regulated advice locally.

The takeaway

The buckets do not change the maths. They change whether you can leave the long money alone.

Pick the one that costs you least, and let the rest wait.