The messages - which will be clearly marked as a test - could warn of flooding, a flu pandemic or even some sort of zombie/nuclear apocalypse presumably.
The first test will occur in Easingwold, North Yorkshire. Over the next two months residents of Glasgow and Leiston in Suffolk will also receive texts.
The plan is part of the National Security Council's (NSC) preparation and planning for emergencies.
A spokesman said the texts would be sent when "we judge that by sending an alert we could prevent loss of life or damage to property", reports the Daily Mail.
Anyone receiving a text will be urged to give feedback and to attend a special focus group.
It will rely on two methods for sending messages - the traditional SMS and cell broadcast (CB) technology that uses a dedicated network.
CB texts will look slightly different from regular messages but ones sent from SMS have raised concerns from security experts.
Chester Wisniewski, senior advisor at data security firm Sophos, told the BBC: "Spoofability will go through the roof if they use 'plain Jane' text messages.
"Anything that carries the gravitas of a national alerts system will be a target for hackers.
"They are opening themselves up to vulnerabilities."
A similar system was recently used in North Carolina, USA, to alert people to the disappearance of a 17-month-old toddler.