Tory and Lib Dem leaders David Cameron and Ming Campbell will both voice their support at the event on Monday, March 26, at Methodist Central Hall, Westminster, at 7-9pm.
Local Works, the campaign group behind the bill, says its introduction will give communities and local councils more power, enabling them to force the government to take action to save local shops, post offices, pubs and other local amenities.
A public meeting to discuss the benefits of the bill will be held on Friday, March 30, at Bolton's Reebok Stadium in Lancashire.
Trade associations including the Association of Convenience Stores (ACS) have spoken out in support of the bill, which has gained cross-party backing from more than 400 MPs and 1,000 local councils.
ACS chief executive James Lowman urged retailers to attend the events. He said: "ACS supports the principles of the bill and encourages retailers to back the campaign to give communities more control. We'll be supporting the rally on March 26."
The bill still has some way to go before it becomes law. It is currently being examined by a cross-party group of 16 MPs who will refine it and it will then be presented to parliament for a third time on April 20.