The law regarding fireworks purchase and usage was relaxed in 2004 and briefly states:
You must not set off or throw fireworks (including sparklers) in the street or other public places.
You must not set off fireworks between 11pm and 7am, except for:
Bonfire Night, when the cut off is midnight
New Year’s Eve, Diwali and Chinese New Year, when the cut off is 1am

See The London Borough of Hillingdon information of fireworks noise nuisance:

Where fireworks are being set off outside the permitted times and are a nuisance, you can report the matter to the Council.
Email: This e-mail address is being protected from spambots. You need JavaScript enabled to view it

Address: 3S/02
Civic Centre
High Street

On Thursday, Friday, Saturday and Sundays there is an out of hours service as follows:

Thursday 2000-0200
Friday, Saturday 2100-0300
Sunday 1900-0100

Telephone: 01895 250111

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