Dumfries and Galloway Council confirmed the 18-month trial programme is scheduled to begin in the autumn, and if successful it will be made permanent.
But before it can be put in action, consultations with Police Scotland, ward members and the community councils will be held.
The measure has been sought to reduce speed, improve pedestrian safety and reduce pollution. It comes after successful pilots in Dumfries town centre and Stranraer. Last year’s report from the communities committee revealed that Annan, Gretna and Langholm are three of the town’s that will implement the slower speed limit.
Annandale South councillor Richard Brodie supports the new speed limit and believes it will be a good thing for the town.
He said: “It is going to be put in place for 18 months, and if it is successful then it will be made permanent.
“If you surveyed people throughout the town the vast majority would support it.
“It’s going to be rolled out across the whole of Dumfries and Galloway over the next few years.”
Meanwhile, Deputy Lord Lieutenant, Hardip Atwal, who lives in Annan, said: “I will be a supporter of it, there are lots of older people and kids around here.
“I just hope if it’s going ahead that everyone sticks to it.
“I know that there are also speed bumps in places already, but that doesn’t seem to bother people. However, I personally don’t think it will work.”
The fatality rate of getting struck by a car at 20mph is significantly lowered when compared to 30mph and parents cite the speed of traffic as a reason for not letting their children walk or cycle to school. Fuel consumption is also re- duced at the lower speed.
A council spokesman said: “With regards to a timeline, once we have completed our consultations with Police Scotland, ward members and the community council and undertaken the detailed design and procurement, we will promote the Temporary Traffic Regulation Order and implement on site – programmed for autumn 2022.”