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Is there any travel restriction during the naturalisation process once the form is submitted. How long can I use the old passport once the form is submitted for UK Naturalisation.

Thanks for your help.

Hi

There is no restrictions on travel. I presume you use NCS and you have your passport with you.
You can use your old passport if your original country allows dual nationality. If you are Indian then you need to surrender your passport as soon as you have done the ceremony.
Anyway sooooo many topics were created with the same questions...

The UK does not place any restrictions on your use of your old passport. However, the country that issued the old passport may have restrictions on its use. For instance, as jaweb has mentioned, an Indian passport should be surrendered within three months of the citizenship ceremony. But that is Indian law, not British law. Similarly, the US requires you to enter the US with its passport if you are a US dual citizen, whereas the UK does not have any such limitation (i.e.: you could enter the UK with a non-UK passport that has been appropriately endorsed).

So, it is down to the country of issue, not the UK, to decide how long the old passport can be used.

You can travel while the application is being considered assuming that you have your passport (and BRP, if applicable) with you.