If you are wondering what a GWF number is, then know that it is a unique application number, which is given to the applicant at the time of submission. It is a reference number that is issued for tracking. *Please note calls to this number will be chargeable at the rate of 75p per minutes plus a connection charge from a BT landline. Jul 15 2019 The GWF number can only be used to track the visa if you have opted for courier service via VFS My friend had applied for UK visa in July 2018 and. Want to check UK visa status online, here you can find how to track UK visa status using GWF.