Applications for British citizenship made after 10 February 2025 will normally be refused for persons who previously entered the UK illegally. The length of time spent in the UK since illegal entry will not mitigate the offence.
“Normally” stands for a very high threshold and many media outlets describe it as a ban on citizenship for illegal entrants. 
The guidance gives a few not particularly helpful examples of the circumstances that can be considered as sufficiently compelling to warrant a positive outcome. The example offered in the guidance refers to a victim of trafficking who entered the UK illegally 14 years prior to applying for citizenship and was granted asylum. The example doesn’t clarify whether it is the absence of guilt on the part of the illegal entrant (the victim of trafficking was not entering the UK of free will and wasn’t responsible for the illegal action) or the time which passes since illegal entry, or both, that brought the matter outside the normal conveyor belt for refusal. And if time was a significant factor, whether a period of less than 14 years would lack the necessary weight.
It is still arguable that asylum seekers who were granted refugee status should not be penalised for illegal entry at the stage of applying for British citizenship. The guidance does not address this, but a section dealing with potential defence against criminal charges of illegal entry may, and in my view, should be read in this context. A refugee should not be penalised for illegal entry or attempted illegal entry if they claimed asylum in the UK without delay and came to the UK directly from the country where their life was in danger or could not claim asylum in any country where they were before arrival in the UK.
It is also arguable, although never stated explicitly in the guidance, that children who entered the UK illegally and were responsible for the offence should not be penalised in their application for British citizenship.
The new guidance on Good Character also confirms that hiring illegal workers is viewed as a more serious offence than working without permission. A person who has employed illegal workers will be refused British citizenship indefinitely, with no expiration date to the offence. A person who worked without permission may be granted British citizenship 10 years after they stopped illegal working.
Finally, since an application for British citizenship may also be refused on the grounds of notoriety, professional curiosity makes this section of the guidance irresistible to immigration lawyers.
Notoriety generally means ill fame or being known (always in certain circles) for a particular eccentricity, a trait of character or habitual behaviour that some people may find unsavoury – there are some notoriously grumpy judges or notoriously bad plumbers in Bedford, but how does this translate into the concept of good character when assessing applications for British citizenship?
The Home Office guidance “Nationality: Good Character Requirement” offers much needed explanation on page 42 by way of example – “King Henry VIII was notorious for beheading 2 (sic) of his wives”. And for additional lucidity adds: “A person does not need to have been convicted of a criminal offence to be notorious, but the scale and level of behaviour must reflect so poorly on their character that it would not be appropriate to grant them British citizenship”. A curious reader might be tempted to check if notoriety may be a ground for a posthumous deprivation of citizenship and if any constitution issues would be raised should the felicitous example of Henry VIII be taken a step further.
