Yes, currently citizens of the UK, EU countries, Australia, New Zealand, Canada, the United States and almost all other nationalities require a visa to visit Indonesia.
At this time, there is a visa on arrival service (VOA) available. The cost is approximately $40 per person - - payable in cash $, £ and Euro also on card.
The maximum period of stay is 30 days which can be extended for a further 30 days. Passports must be valid for at least 6 months at the day of exit, and should contain at least one empty page on the day of arrival.
You can also apply for a visa online in advance at www.evisa.imigrasi.go.id
For the latest information, please check the embassy website at www.consular.indonesianembassy.org.uk/visa
These forms are required to be completed up to 3 days prior to your arrival in Indonesia. Airport Wifi is notoriously unreliable and we therefore recommend that you complete these forms before you travel to Indonesia. This can now be done on one website https://allindonesia.imigrasi.go.id/
Once completed you will be provided with a QR code which you can save on your phone or other devices ahead of time to show at all Indonesian airport arrival points.
There is a now a sustainability fee that needs to be paid by all arrivals in Bali. You can pay it on arrival, however it will save you time if you take care of it in advance. It's not a lot (approx £8 per person) but the idea is that your contribution will go towards the maintenance the culture and the natural environment in Bali.
Please visit www.lovebali.baliprov.go.id if you wish to make the payment in advance of your arrival.