Please, describe the British Citizenship eligibility.

There are different routes to citizenship in the UK and it depends on your circumstances as to how difficult it is.

Over the last few years, the Immigration Rules have been subject to ongoing changes and new and stricter requirements have been added in some cases.

Before becoming British you usually have to acquire Indefinite Leave to Remain ("ILR") or "settle", this essentially means you do not have any restrictions on staying in the UK. There are exceptions, for example, European nationals need to acquire Permanent Residence first instead. A year after receiving ILR you will be able to apply to become a British citizen.

To acquire ILR you will have to show that you are in the UK lawfully. This might be in a number of ways, you might be here as a student, as a Tier 2 worker, under Tier 1 as an entrepreneur or investor. You might have come to the UK as a spouse or family member. Different routes require you to have completed different lengths of lawful residence before you can apply for ILR (so in general family members can apply for ILR more quickly). For example, if you have been in the UK for five years on a Tier 2 visa you can apply to settle. The Tier 1 investor route offers faster routes to the settlement, depending on how much you have invested in the UK.

These are just examples of how to eventually become eligible for British citizenship, advice should be sought for specific applications.
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