A change in the law came into effect at the end of 2019, according to which, in the event of purchase-sale of a MV or change of registered address, the registration plates of automobiles no longer need to be changed. This automatically means that in these cases, the vignette remains valid without any additional actions by the driver.
Regardless, if you choose to voluntarily change your vehicle's registration plate, you will have to transfer the vignette as well. A well-known fallacy among drivers states that, having once paid a vignette fee, it remains valid even in the event of change of number plates. In fact, this is not so – the e-vignette is now issued to a vehicle with a certain registration plate and is only valid for that vehicle. For this reason, should the number plate be replaced, the driver must state this before the regional road administrations of the Road infrastructure agency within three business days or do that electronically at info@bgtoll.bg. (A sample application can be downloaded here https://www.bgtoll.bg/za-nas/zaavlenia). If you miss the 72-hour deadline, you will lose the right to be issued a new free vignette.
In this regard, we need to warn you to be especially careful when buying an e-vignette and entering the vehicle's data, because if they are entered incorrectly, the issued vignette will also feature wrong data. In this case, presently you can neither make an amendment, nor obtain a reimbursement for the amount. Your only option would be to invest in a new vignette.