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An employer match is an immediate, guaranteed return on your contribution - and it is the highest-return component available in most people's finances.

• Contributing less than the match threshold is declining a raise that requires no additional work from you.
• Match is on the employee deferral only - contributing more than the match cap still helps you, just without extra employer money.
• The match vests over time. Leaving before the vesting schedule completes forfeits the unvested portion of the employer contribution.
• Some employers contribute regardless of your deferral, but most require you to contribute first.

Note. Before increasing any other savings or debt repayment, verify you are capturing the full available match. There is no comparable guaranteed return.

The comparison depends entirely on the difference between your current and future tax rates. Contributing pre-tax while earning a high salary and withdrawing during a lower-income retirement usually favours traditional. Contributing early in a career, while earnings are lower, often favours Roth - and young savers frequently underestimate how much their income will rise.

• Hedging is legitimate. Splitting contributions between the two hedges against an uncertain future tax rate.
• State tax matters. Moving between states in retirement changes the calculation independently of federal rates.
• Roth conversions - moving pre-tax money to Roth in a low-income year, paying tax now at a reduced rate, is a deliberate strategy worth modelling with an adviser.

• Annual limits are set by the tax authority and rise periodically. The deferral limit for employees and the separate higher limit including employer contributions both change - check the current tax-year figures rather than relying on last year's.
• Catch-up contributions are permitted from age 50, with an additional enhanced allowance in a narrow window around the early sixties for those eligible.
• The limit is per person across all plans, not per employer.
• Other retirement accounts interact - contributing to a workplace plan can reduce what you may contribute to other tax-advantaged accounts in the same year.
• Plan-level limits - some plans impose lower caps than the legal maximum.

Note. Do not work from remembered figures. Confirm the current-year limits before making year-end contributions, because an excess is returned with penalties if it is not corrected promptly.

1. Constant contribution - in reality raises, bonuses and job changes all move the figure.
2. Constant return - sequence risk means the actual outcome can differ substantially from an average-rate projection, particularly in the years around retirement.
3. Fees are deducted - fund expense ratios and plan administration charges compound as a drag. A 0.5% fee difference on a long accumulation period is worth tens of thousands.
4. Contribution limits rise - a projection that holds contributions flat in nominal terms is conservative, since limits are indexed upward.
5. Treatment of the balance at retirement - pre-tax balances are worth less than the headline number once income tax is applied. Model the after-tax figure.

1. Capture the full match before anything else.
2. Increase with every pay rise - directing a portion of each raise to the plan preserves the increase in take-home while raising savings without feeling like a cut.
3. Roll old plans together when you change employer, to avoid stranded low-quality funds and scattered fees - but check that moving does not forfeit existing employer money or valuable features.
4. Review fund selection. Many participants stay in a default fund that does not match their horizon. Lower-cost index options within the plan are typically preferable.
5. Avoid withdrawing early. Distributions before the qualifying age are generally subject to income tax plus a penalty, and the lost compounding is usually far larger than the amount withdrawn.
6. Loans against the plan carry interest paid to yourself, but the balance is reduced while the loan is outstanding, and leaving your job often triggers immediate repayment.