How often to replace your toothbrush or brush head
Replace a toothbrush every 3 to 4 months, the ADA says, and a brush head about every 3, or sooner if bristles fray. Signs it is time, and which heads fit.
Oohunt Deal Desk · Buying guides · September 17, 2026 · 6 min read
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Replace a manual toothbrush every three to four months, and an electric brush head about every three. Three to four months is the American Dental Association’s guidance, and Oral-B and Philips recommend a new head every three months. Replace either sooner if the bristles have started to fray.
Three months pass quickly, and a brush wears so gradually that it is easy to miss, which is why many people keep theirs far longer. The rest of this guide covers how to tell a brush is worn out and how to make sure the next one is ready when it is due.
When to replace your toothbrush sooner
The bristles splay. Look at the brush head-on. If the bristles lean outward past the edge of the head, they are no longer pointing where you are brushing. Brushing hard wears bristles out faster.
The indicator bristles have faded. Many heads have colored indicator bristles. On Oral-B heads they fade about halfway when the head is due, and on some newer heads they change color instead. On Sonicare heads that have them, replace the head when the blue indicator bristles wear, and some Sonicare handles also flash a reminder.
You have had a cold sore, or a brush shared a holder with someone sick. A healthy person is unlikely to reinfect themselves from their own brush, but ADA News advises a new one after a cold sore, for anyone severely immunocompromised, and for every brush in a holder shared with someone who was ill. Some people replace a brush after strep throat or the flu anyway; the ADA does not list that as necessary, but a new brush costs little.
It is a child’s brush.Children’s brushes can wear out faster, especially if they get chewed, so check the bristles regularly.
Why a worn brush cleans less
The ADA says a toothbrush becomes less effective as its bristles wear. Splayed bristles no longer point where you aim them, including along the gumline, so the same two minutes of brushing does less.
How often to replace an electric toothbrush head
About every three months: Oral-B and Philips both recommend a new head every three months. The handle of an electric toothbrush is built to outlast many heads, and a worn head is easy to forget because the handle still looks new. Some Sonicare handles flash a reminder when a head is due.
Which replacement heads fit your toothbrush
Heads only fit their own handles. Oral-B heads do not fit Sonicare, and within a brand, some ranges are closed: Oral-B iO heads fit only iO handles, Philips One by Sonicare heads do not fit other Sonicare handles, and Waterpik Sonic-Fusion heads fit only Sonic-Fusion. Check the model on your handle before you buy.
How many to buy at once
At one every three months, a person goes through four brushes or heads a year. A 4-pack is a year’s supply, and an 8-pack covers a couple for a year. Buying the year up front is also the easiest way to make sure the next one is in the bathroom cabinet on the day it is due.
Looking after a brush between replacements
Rinse it well after brushing, store it upright, and let it air dry. The ADA advises against routinely covering a brush or keeping it in a closed container, so save the travel cap for travel. If brushes share a holder, keep them from touching, and never share a brush.
Brush heads and toothbrushes worth a look
A replacement head for each of the common handles, and a manual option. Prices change often, so check the current one on Amazon.
What we would buy (6)
Affiliate links
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Oral-BiO Ultimate Clean replacement heads, 2-pack
Opens Amazon in a new tab.Made for Oral-B iO handles, which take no other heads. The one to stock if you own an iO.
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Oral-BPro CrossAction replacement heads, 8-pack
Opens Amazon in a new tab.For Oral-B rechargeables other than iO and Oral-B's sonic models, with indicator bristles that show when the head is worn. Eight heads is two years for one person.
- Check price on Amazon
Philips SonicareA3 All-in-One brush heads, 4-pack
Opens Amazon in a new tab.Four heads for Sonicare click-on handles: a year's supply for one person at one every three months.
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Philips SonicarePhilips One by Sonicare brush heads, 2-pack (BH1022)
Opens Amazon in a new tab.Made for Philips One by Sonicare toothbrushes, and they do not fit other Sonicare handles. Two heads, a six-month supply.
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WaterpikSonic-Fusion full-size replacement heads, 2-pack
Opens Amazon in a new tab.Only for Waterpik's Sonic-Fusion brush-and-flosser, which uses its own heads.
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Oral-B3D White manual toothbrushes, 4-pack
Opens Amazon in a new tab.For a manual brush, a 4-pack is a year of replacements for one person.
No prices or star ratings here. Prices change daily and we do not track them, so Amazon shows you the current one. Nothing on this list has been tested.
Common questions
How often should you replace your toothbrush?
Every three to four months, which is the American Dental Association's guidance, or sooner if the bristles are frayed or matted.
How often should you replace an electric toothbrush head?
About every three months. Oral-B and Philips both recommend replacing heads every three months. The handle is built to outlast many heads; it is the head that wears out.
How often should you replace a Sonicare brush head?
Philips recommends every three months of normal use, or when the blue indicator bristles wear. Some Sonicare handles also flash a replacement reminder.
How often should you replace an Oral-B brush head?
Every three months, or once the indicator bristles have faded about halfway (some newer heads change color instead).
Should you replace your toothbrush after being sick?
Usually it is not necessary, because the antibodies you made while sick make reinfection unlikely. ADA News does advise a new brush after a cold sore, if you are severely immunocompromised, or if a sick person's brush shared a holder with others.
Do Sonicare brush heads fit an Oral-B toothbrush?
No. Each brand's heads only fit its own handles, and within a brand, some ranges are separate too: Oral-B iO heads fit only iO handles, Philips One by Sonicare heads do not fit other Sonicare handles, and Waterpik Sonic-Fusion heads fit only Sonic-Fusion.
Another thing that needs replacing on a schedule is a water filter: see how often to change a Brita filter. More oral care, from brush heads to water flossers, sits in health & household.