Lowes, Home Depot, eBay and local home appliance stores all have sales on appliances. Online appliance stores also have sales, but the cost of shipping must be factored in to the final price.
Large home improvement stores often have sales on appliances because they sell a large volume so they can afford to sell at a lower price. Local appliance dealers sometimes use social media and Craigslist.org to advertise sales. Some stores can offer better pricing if a washer and dryer set are bought together. Other services such as free delivery and removal of old appliances can add to the value of the discounted appliances.