Increase contributions on a fixed schedule, not when it feels affordable

Build in automatic contribution increases so lifestyle inflation does not silently consume your investment capacity.

Why it works

Lifestyle inflation is the tendency for spending to rise with income, consuming the marginal dollar before it reaches investment. Automating increases at the moment of a raise — before the new income is absorbed into a higher spending baseline — prevents hedonic adaptation from converting the raise into invisible consumption. The mechanism mirrors "Save More Tomorrow" (SMarT): pre-commitment at a moment of positive change removes the future willpower requirement.

How to do it

1. Each time income increases, redirect at least half the after-tax increment to the investment before it hits the spending account.
2. Alternatively, set an annual 1% contribution increase in January, regardless of income change.
3. Review the total contribution rate yearly — but the amount going up should be automatic, not subject to how good the year felt.

Evidence

The SMarT program demonstrated that pre-committed future increases dramatically raised savings rates — participants increased contributions without experiencing the loss that immediate increases would have triggered. (rct)

SMarT evidence is from employer plan design; applying to self-managed personal investing requires self-administered pre-commitment, which may have lower compliance.

Sources

• Thaler & Benartzi (2004), "Save More Tomorrow," Journal of Political Economy

Common mistake

Waiting until "I can afford it" to increase contributions — which typically means waiting until spending is fully established at the new income level and there is nothing left to save.