During the implementation period, EU law will continue to apply.
The Financial Conduct Authority (FCA) has published information for firms when the UK enters the implementation period.
When the UK leaves the EU at 11pm on 31 January, the country will enter an implementation period which is due to last until the 31 December 2020.
During the implementation period, EU law will continue to apply.
The FCA advises that this means there will be no changes to the reporting obligations for firms including those for MiFIR transaction reporting.
Andrew Bailey, chief executive of the FCA, said: "The work the FCA has undertaken, along with government and the Bank of England, ensured the financial services sector was one of the best prepared industries for any of the possible Brexit outcomes.
"The implementation period gives firms a period of certainty while negotiations are continuing on our future relationship with the EU.
'The FCA intends to use this time to work with government, the Bank of England, firms and other regulators to ensure the financial services industry is ready for the end of 2020.
"We will continue to keep firms and consumers updated on any changes that will impact them."
Michael McKee, partner at DLA Piper, added: “While firms with a UK presence should all be well aware that the timeline for entering the Temporary Permissions Regime expires today we know that there are firms operating from Europe remotely who may not have appreciated this.
"One thing we are seeing is an increase in the opening of representative offices in the UK by many continental European and Irish entities to help them bring in UK business to their home locations.”
The FCA emphasises that all financial services firms should consider how Brexit will impact their business and what action they need to take to be ready for 1 January 2021 to minimise risks to customers.
Firms can call the FCA Brexit information line (0800 048 4255) if they have any further questions.
