Ebay is strict when it comes to bid retraction. Each bid placed on an item creates a binding agreement. However, there are certain times eBay allows bid retraction. Additionally, the seller can choose to retract a buyer's bid at any time, whether the reason falls in line with eBay's retraction guidelines or not. Undoing a bid on eBay will relieve you of the obligation to purchase the item.
Review eBay's rules for bid retraction. Generally, you're allowed to retract a bid only due to a typographical error (entering the wrong bid amount), or due to the item description of terms of the sale changing after you place a bid. Bid retraction is also available if you cannot contact the seller.
Fill out eBay's Bid Retraction form (see Resources). You'll need to log in to your eBay account to fill out this form. Type in the item number and select the reason for retracting your bid. Your choices are "Entered wrong amount," "Item description changed" or "Cannot contact seller." If you don't know the item number, click on "My eBay" and click "Bidding" to view the item number associated with the auction.
Click "Retract" to retract your bid. If the retraction is due to a typographical error, eBay requires that you re-bid the correct amount immediately.
Contact the seller of the item if your reasons for retraction are not in line with eBay's rules. Use eBay's Contact Seller link on the item page. It's the seller's choice whether to retract the bid. Be polite and explain your reasons when sending the seller a message.
If the auction has less than 12 hours remaining, eBay will retract only your most recent bid on the item. Your previous high bids are not retracted unless you initiate the retraction with more than 12 hours remaining in the auction.