A campaign for a complete ban on smoking in all NHS buildings and grounds has been launched by Public Health England (PHE).
PHE said a "tobacco-free NHS" would encourage patients, visitors and staff to give up the habit, along with more support to help them quit.
Many hospitals are already smoke-free in their buildings and grounds but some people still flout the rules.
Duncan Selbie, chief executive of PHE, said "25% of patients in hospital are smokers," and a smoke-free environment would be beneficial for everyone.
He added: "I believe we can make the NHS a place that provides a supportive tobacco-free environment for patients, staff and visitors, where helping people quit is fully integrated into their treatment."
In an open letter to all NHS trusts Mr Selbie wrote: "I am asking for your help to reach smokers who are in your hospital waiting rooms, consulting rooms and beds.
"There is a clear opportunity to achieve significant short-term savings and reduce demand."
Tobacco is the single biggest cause of premature death in England, costing the NHS an estimated £2 billion every year and another £1.1 billion in social care, according to PHE.
Around seven million adults in England smoke and for every death caused by smoking there are around 20 suffering from diseases.