Hello, my name is Jim and I am a qualified lawyer happy to help you today.
If there is a child arrangements order saying your Son lives with you then you can take him abroad for up to 1 month without the consent of the Father.
If there is no such order then you will need either your ex's written consent to travel abroad with your Son, or you will have to apply to the local family court for an order to travel. I would recommend you make the application as soon as possible if you plan to travel in the next few weeks.
You can apply online here depending where you live :
If that site does not let you apply, you need to fill in and send form C100 (attached) to your local family court centre. You will also need to pay the fee of £215 when you file the form (either a cheque payable to HMCTS or you can pay on the telephone if you contact the court. Alternatively if you go to the court in person you can pay over the counter).
You will need 3 completed copies of the form (fill out one and copy it another two times) so the court can process it for you. The court will list a short hearing where you attend and ask the judge for an order in relation to your travel details. If approved then you are allowed to travel and your ex will be served a copy of the order.
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