It used to be a fine-able offence to leave your rego sticker on the window after it had expired. So now we have no stickers – are you allowed to keep the old one on?
Yes and No. QLD law says if your vehicles is under 4500 kg (4.5 tonne) – which is your car or van, you can LEAVE THEM ON. Light trucks and up need to remove old labels.

Fast Facts.
a) It used to cost QLD transport $3.5m each year to print labels. (not sure how much the cameras cost – presumably a lot but less ongoing costs)
b) WA changed to electronic rego in 2010, SA in 2011, and NSW in 2013.
c) Not all electronic rego cameras are fixed – there are some that are placed on government and police vehicles. So your rego is constantly checked – even when the office clerk goes to the shops to collect the coffee!
d) Governments report a massive spike in fines – usually catching those people who for many years have avoided paying rego as their own private rebellion- BUT it’s now easier than ever to forget to pay and then get stung.
e) State governments increased the fines for unregistered and uninsured vehicles at the same time as moving to the electronic system! (Don’t forget, an unregistered car is an uninsured car! (CTP)
f) It’s easy to check your rego status at www.qld.gov.au/checkrego