How to Clean a Bottle Brush? | Stop Bacteria Buildup

For the full breakdown, see our best Electric Bottle Brush guide.

A dirty bottle brush defeats the purpose of cleaning bottles. Left damp, the bristles trap milk residue and become a breeding ground for germs that you then spread onto the very items meant for your baby. The right routine takes about two minutes and prevents that problem entirely.

Here’s the short version: rinse, wash, dry. Repeat that cycle faithfully, and your brush stays as clean as the bottles it scrubs.

The Daily Rinse

After each use, hold the brush under warm running water and work the bristles with your fingers to dislodge loose residue. This takes seconds but prevents formula or milk from drying onto the brush and hardening into a film that soap struggles to remove later.

Make this a habit rather than an occasional gesture. A brush left sitting in a sink or basin after use gives bacteria a head start.

The Deep Wash: Every Few Days

The CDC guidance for infant feeding items is clear: wash the bottle brush itself every few days, either in a dishwasher with hot water and a heated drying cycle if the brush is dishwasher-safe, or by hand with soap and warm water.

For hand washing:

• Squirt mild dish soap onto the bristles and work it through with your fingers or against the sink edge
• Pay attention to the base of the bristles and the handle, where residue collects
• Rinse thoroughly under running water until no soap remains
• Shake off excess water, then set the brush in a clean, well-aired spot to dry completely

A brush that goes into storage while still damp invites the exact buildup you are trying to avoid.

Dishwasher Use: Only If It’s Labeled Safe

Not every bottle brush belongs in a dishwasher. Check the label or product instructions before you load one. Brushes that are dishwasher-safe should go on the top rack or in a utensil holder, away from the heating element. Some manufacturers specify low-temperature cycles around 60°C, so high-heat settings can damage certain models.

When that is not possible, hand washing with soap and warm water is the safer default.

What Not to Do

• Do not boil, steam, or microwave-sterilize a brush unless the manufacturer explicitly says it is safe — heat can warp bristles or crack handles
• Do not use bleach or aggressive cleaning agents unless the instructions allow them
• Do not assume one brush behaves like another; instructions vary by model and material
• Do not store a damp brush — moisture is the enemy of clean

Bottle brushes are simple tools, but each one has its own limits. When in doubt, the gentlest method that gets the brush clean is the right one.

FAQs