# Water flosser vs electric toothbrush: do you need both? Source: https://brushandfloss.co.uk/blog/water-flosser-vs-electric-toothbrush Published: 2026-10-11 Publisher: Brush and Floss **In short:** They do different jobs. An electric toothbrush cleans the outer, inner and biting surfaces of your teeth; a water flosser rinses between teeth and along the gumline. A water flosser is not a substitute for brushing twice a day as the NHS advises. If you want both in one unit, combos such as the Waterpik Sonic-Fusion 2.0 put a sonic brush and a flosser on the same handle. People sometimes ask whether a water flosser can replace their toothbrush, or whether an electric toothbrush makes flossing unnecessary. The short answer to both is no. Brushing and cleaning between teeth do different jobs, and NHS guidance includes both. This guide explains what each device is designed to do, how they fit together in a routine, and whether a combined unit is worth considering if counter space is tight. It uses listing facts for the products mentioned and makes no health promises. ## What each device does An **electric toothbrush** cleans the surfaces of your teeth you can reach with bristles: the front, the back and the biting surfaces, plus the gumline. It has a timer to help you brush for the two minutes the NHS advises. A **water flosser** cleans the spaces between teeth and along the gumline with a pulsing jet. It cannot scrub the flat surfaces of teeth the way a brush does. NHS guidance covers cleaning between teeth with floss or interdental brushes; ask your dental team whether a water flosser suits you for that job. ## Why they are not substitutes Toothpaste matters. The NHS advises brushing with fluoride toothpaste, then spitting rather than rinsing. A water flosser uses plain water, so it cannot deliver fluoride to your teeth the way brushing does. Equally, bristles struggle to reach right between tight teeth. That is why cleaning between teeth is a separate step, whether with floss, interdental brushes or a water flosser. Note: Persistent bleeding, sore gums or a bad taste are reasons to see a dentist. Neither device diagnoses or treats a problem. ## Combo units compared with separate devices The **Waterpik Sonic-Fusion 2.0** puts a sonic toothbrush and a water flosser in one handle on a countertop base. Its listing describes three modes (brush, floss, or both), a two-minute brushing timer with a 30-second pacer, two brush speeds, 10 flossing pressure settings, 60 seconds of flossing time and a 16 oz removable reservoir, roughly 470 ml. It comes with a toothbrush travel case. A separate sonic brush such as the **Sonicare DiamondClean 9000** has more brushing settings and a travel charging case, but you would need a separate flosser too. | | Waterpik Sonic-Fusion 2.0 | Sonicare DiamondClean 9000 | | --- | --- | --- | | Type | Sonic brush and water flosser | Sonic toothbrush | | Modes | Brush, floss, or both | 4 modes, 3 intensities | | Flossing | 10 pressure settings, 60 seconds | None | | Timer | 2 minutes with 30-second pacer | Built in | | Reservoir | 16 oz removable | Not applicable | | Travel | Toothbrush travel case | USB charging travel case, up to 14 days stated | Combo and separate brush from the listings [Compare sonic toothbrushes](https://brushandfloss.co.uk/best/best-sonic-electric-toothbrush) ## Pros and cons of a combo If you are having trouble with a combo, see our [Waterpik Sonic-Fusion problems](https://brushandfloss.co.uk/blog/waterpik-sonic-fusion-problems) guide. - **Pro:** one device and one base on the counter. - **Pro:** brush and floss in one routine, which can help you remember both. - **Con:** the base needs a socket and space by the sink, so it is less portable than a separate brush. - **Con:** if one part fails, you lose both functions until it is fixed. - **Con:** fewer brushing modes than a premium standalone brush. ## Putting both in a routine Some hygienists suggest cleaning between teeth before brushing; follow your own dental team's advice on order. Our guides on [using an electric toothbrush](https://brushandfloss.co.uk/blog/how-to-use-an-electric-toothbrush) and [using a water flosser](https://brushandfloss.co.uk/blog/how-to-use-a-water-flosser) cover each step in detail. For a standalone brush, see our [premium electric toothbrush guide](https://brushandfloss.co.uk/best/best-electric-toothbrush). 1. Clean between your teeth with the water flosser, starting on a low pressure and working tooth by tooth. 2. Brush for about two minutes with fluoride toothpaste, spending about 30 seconds on each quarter of your mouth. 3. Spit out the toothpaste and do not rinse, as the NHS advises. 4. Empty and dry the flosser reservoir, and rinse the brush head. ## Frequently asked questions **Can a water flosser replace brushing?** No. Brushing with fluoride toothpaste twice a day is the core of NHS advice, and a flosser cannot do that job. **Do I need a flosser if I have an electric toothbrush?** You still need to clean between your teeth. Floss, interdental brushes or a water flosser can do that; ask your dental team which suits you. **Is a combo unit as good as two devices?** It does both jobs in one unit, but usually with fewer brushing modes than a premium standalone brush. **Can I take a combo on holiday?** The Sonic-Fusion 2.0 brush comes with a travel case, but flossing needs the countertop base, so it is less travel friendly. ## Buying guides on this topic - https://brushandfloss.co.uk/best/best-sonic-electric-toothbrush - https://brushandfloss.co.uk/best/best-electric-toothbrush - https://brushandfloss.co.uk/best/best-electric-toothbrush-travel-case ## Sources - [NHS: How to keep your teeth clean](https://www.nhs.uk/live-well/healthy-teeth-and-gums/how-to-keep-your-teeth-clean/) - [Waterpik UK](https://www.waterpik.co.uk/)