How long does take to bring my old number to smarty

[MSF]

@Mukhtar_2018583 Normally the next business day by 5pm. Don't forget that Monday 01 May didn't count as it was a Bank Holiday.

[Chalkychap]

The procedures for bringing your number to SMARTY are covered online at: 
https://help.smarty.co.uk/en/articles/4227325-cancel-my-old-phone-number-and-account-with-my-previou.... 

The timescale is covered online at: 
https://help.smarty.co.uk/en/articles/7172594-when-will-my-number-be-transferred.