Guide
Switching provider
Move without missing invoices.
One number, one provider
A number can only sit with one provider. The new one can only take over once the old one releases it.
The migration key
The old provider creates a key; the new one takes over with it. One key per number, so often two.
What the old one may ask
Sometimes written authorisation or paid invoices. So ask for the key in time.
Doesn't work?
Then the old registration is removed and recreated. Expect a short pause in receiving.
Check afterwards
Make sure both numbers are with the new provider. A forgotten VAT number is the classic mistake.