ETFCompass logo ETFCompass
A calm, long-horizon investing blog for ordinary people.

Rebalancing with contributions: the easiest method for beginners

Published: 2026-04-18

Rebalancing sounds like you must sell something. You often don’t. If you invest regularly (monthly, quarterly), the easiest beginner method is to use new money to buy more of what’s below target, and less of what’s above target.

What rebalancing is (one sentence)

Rebalancing means bringing your portfolio back toward your chosen target weights, for example 80% stocks / 20% bonds.

The problem beginners face

Markets move. If stocks rally, your portfolio might drift from 80/20 to 86/14. If stocks fall, it might drift to 74/26. Without a rule, people tend to do the opposite of what helps: buy what already went up, and avoid what went down.

The easiest method: “rebalance with contributions”

Each time you add money, you direct your contribution to the asset that is most below target. This slowly pulls your weights back, without selling.

A simple example

Instead of buying more stocks (because they “feel good”), you buy mostly (or entirely) bonds until you’re closer to 80/20 again.

A 3-step rule you can actually follow

  1. Pick targets once (example: 80/20 or 60/40). Write them down.
  2. On contribution day, check your current weights (your broker often shows this, or you can do a quick spreadsheet).
  3. Buy the underweight part with the new money (the one furthest below target).

When this works best

When you may still need to sell

Rebalancing with contributions has limits. You may need to sell (or do a bigger rebalance) if:

Two guardrails (to keep it calm)

The beginner takeaway

If you invest regularly, you can do most of your rebalancing by simply buying what is below target. It’s simple, it avoids unnecessary selling, and it naturally pushes you toward “buy low / buy high” behavior without trying to predict anything.

Related