Public Health England (PHE) said that smoking rates among adults in England are expected to fall from the current level of 14.9% to around 10% by 2023.
The number of smokers in England has fallen by more than a million since 2014, it added.
The estimate comes as the health body launched its annual Stoptober campaign, encouraging smokers to join a mass quit attempt in the month of October.
Officials are encouraging smokers not to “go cold turkey” as the method may hamper a person’s chance of successfully quitting.
PHE said that the best way to quit is with expert help from local stop smoking services together with stop smoking aids.
For this year’s campaign, PHE is offering an online “Personal Quit Plan” to help smokers find the right support to help them kick the habit.
The new tool will recommend a range of options to smokers including face-to-face support, nicotine replacement therapies like patches, gum or inhalers, and e-cigarettes.
Last year’s Stoptober campaign was the first to encourage smokers to try an e-cigarette in a bid to kick the habit.
PHE said that e-cigarettes are used by an estimated 3.2 million people across Britain.
The health body estimates that of the 6.1 million smokers in England, around six in 10 want to quit.
It said that every year around 400,000 smokers quit successfully in England - the equivalent of around one every 80 seconds.
The Stoptober campaign began in 2012 and is based on research that if smokers can go for 28 days without a cigarette then they are five times more likely to quit for good.
Dr Jenny Harries, deputy medical director at PHE, said: “There are many different types of stop smoking support available, so it can be difficult for a smoker to know what will work best for them.
“The important thing is not to be put off trying to quit even if you have not managed to in the past.
“This year, Stoptober can help you find a combination that could work for you.
“We predict that thousands of smokers will quit every day over the next 10 years - I urge smokers not to get left behind for the benefit of their health.
“Join in, find your best way to quit, and start your 28-day journey to becoming smoke-free.”
The new PHE estimates come from its Health Profile for England report which states that the prevalence of smoking in adults has declined from 19.9% to 14.9% in the last seven years.
If this trend continues, it will reduce to between 8.5% and 11.7% by 2023, the authors suggest.
Visit www.nhs.uk/oneyou/stoptober to use the Personal Quit Plan and to find out more about the support available.