Boots has said its store closure programme will affect around 200 locations over the next 18 months, mostly local pharmacies.
The shop's owner, Walgreens Boots Alliance, has confirmed a plan that will see local pharmacy branches shut down where there are other stores nearby.
Boots has not said how many jobs will be affected by the move, with the chain promising to find new roles for staff wherever possible.
UK managing director Sebastian James said: "We believe this is the right thing to do as it means that we can invest more in staffing those stores while not reducing our 90% coverage within a 10-minute drive of a Boots.
"We do not anticipate a significant effect from this activity to colleagues as we will redeploy the overwhelming majority to neighbouring stores."
Boots would not specify to the Mirror which locations were at risk.
"We cannot confirm specific stores at this stage as we have only started the optimisation process," a spokesman said.
Boots said it was part of a wider change to their store portfolio, and not a case of the chain pulling back.
"We continue to open new stores where we believe there are communities that would benefit from a new Boots - for example the new Covent Garden flagship (creating 130 new jobs) which opened yesterday,” James said.
He added: “There’s no doubt that trading conditions are tough on the High Street and healthcare and retail are facing a challenging reality. Boots is not immune to these pressures, however we have a remarkable brand and I am continually amazed by the extraordinary deep love and respect people have for Boots.
"We’re still a very successful company with a phenomenal presence in the UK but we need to take some tough decisions to transform the fundamentals of our business, building on our 170-year legacy, to ensure our future growth.”
Usdaw, the union for retail workers, called for the company to enter talks and said it was "worrying" news for employees.
National officer Daniel Adams said: "We urge the company to engage with Usdaw as the trade union for Boots retail staff to ensure that all avenues to minimise job losses are explored during this critical time.
"This issue is not confined to Boots; our high streets are in crisis and we need the Government to adopt a clear and coherent strategy for retail, to address the worries and concerns of shop workers and our members."
