In line with the UK and other Channel Islands, the Bailiff has directed that Islanders observe the silence at 11 am.
Flags should also remain at half mast until at least 8 pm, being raising to full mast before 8 am on Friday.
A total of 22 people – a number of them children – died and 119 were injured in the blast outside an Ariana Grande concert.
Manchester-born Salman Abedi has been named as the suicide bomber who carried out the attack and his brother and father have since been detained in Libya.
