The short answer is neither straight after. The NHS advises against using mouthwash straight after brushing your teeth, even if it is a fluoride mouthwash, and suggests using it at a different time of day instead, for example after lunch. The reason is the fluoride from your toothpaste, which you want to leave on your teeth for as long as possible.
Why the timing matters
When you brush with fluoride toothpaste, a concentrated layer of fluoride is left on your teeth. The NHS advice is to spit out the excess toothpaste after brushing but not to rinse your mouth with water, because rinsing washes that fluoride away and makes it less effective. Swilling mouthwash around straight after brushing has much the same effect as rinsing with water.
The government guidance written for dental teams in England, Delivering better oral health, says the same about fluoride mouthrinses. It advises using them at a different time from toothbrushing, so that the fluoride stays in the mouth for longer, and treats a fluoride rinse as something extra on top of brushing twice a day rather than a replacement for it.
What about using mouthwash before you brush?
The NHS guidance does not say anything specific about rinsing before you brush. The problem it describes is washing away toothpaste fluoride after brushing, and that does not apply if you brush afterwards, so rinsing first is a reasonable option if it suits your routine better. If your dentist has given you specific advice, follow that.
Do dental experts all agree?
Not completely. In 2026 the Oral Health Foundation said that a mouthwash aimed at gum health can be used after brushing, while a fluoride mouthwash for protecting against decay should be used at a different time of day. The NHS advice is the simpler of the two: whichever mouthwash you use, keep it away from the time you brush.
What this means for a fluoride free mouthwash
A fluoride free mouthwash such as No Fluo adds no fluoride, so using it straight after brushing would rinse away the fluoride from your toothpaste without putting any back. The best time to use it is at another point in the day, for example after lunch or after a coffee, when you want your mouth to feel fresh.
Safety: do not swallow. No Fluo contains tea tree oil, which is harmful if swallowed. Rinse and spit it out, and keep the bottle out of reach of children.
A simple daily routine
- Brush your teeth twice a day, including last thing at night, with a fluoride toothpaste as the NHS recommends.
- Spit out the excess toothpaste, but do not rinse with water.
- Clean between your teeth with floss or interdental brushes.
- Use mouthwash at a different time of day, such as after lunch.
- If you use a fluoride mouthwash, do not eat or drink for 30 minutes afterwards.
Frequently asked questions
Should I rinse with water after brushing my teeth?
No. The NHS advises spitting out the excess toothpaste but not rinsing, because rinsing washes away the concentrated fluoride left on your teeth and reduces its effect.
Can I use mouthwash straight after brushing?
The NHS advises against it, even with a fluoride mouthwash. Use mouthwash at a different time of day, for example after lunch.
When is the best time to use mouthwash?
At a time when you are not brushing your teeth. The NHS gives after lunch as an example. This keeps the fluoride from your toothpaste on your teeth for longer.
Is mouthwash necessary?
Mouthwash is an optional extra rather than a must. The core NHS advice is to brush twice a day with fluoride toothpaste and to clean between your teeth. Many people like mouthwash for a fresh feeling, and some types are recommended for particular needs, such as an alcohol free mouthwash if you have a dry mouth.
Related guides
- How to use mouthwash correctly
- Is alcohol free mouthwash better?
- Alcohol free mouthwash: No Fluo, alcohol free and fluoride free
- All guides