It comes as the nation starts a period of mourning to mark the death of its former monarch on Thursday afternoon.
The Exchange confirmed trading will also “close at the normal times” on Friday afternoon.
Trading will continue at the usual times during the national mourning, which is expected to continue for roughly 12 days.
The Exchange did say, however, it will close if a public or bank holiday is announced for England and Wales.
On Thursday, the London Stock Exchange Group said: “We are deeply saddened at the passing of Her Majesty Queen Elizabeth II.
“Our sympathies and condolences are with the royal family.”
Currency trading began strongly on Friday morning, with the pound rising by 0.9% to 1.159 against the dollar, slightly arresting its recent tumble, which saw the UK currency hit 37-year lows on Wednesday.
Most companies are expected to continue operations as normal on Friday morning.
However, historic department store chain Selfridges said it would shut its doors on Friday as it led business tributes to the Queen.
It said it intends to reopen stores on Saturday with their usual opening hours.