Teeth whitening typically lasts anywhere from one to three years, depending on how well you care for your teeth and how often you whiten them. Factors such as smoking and drinking beverages that stain teeth, like coffee, tea, and red wine, can affect how long the whitening lasts. Regular brushing and flossing can help maintain the whitening effects for longer periods. Additionally, touch-up treatments can be used to maintain your whitening results over time.