Craigslist.org–a popular website among those buying, selling or renting goods and services–assigns posting numbers to each ad placed on the site. The ad numbers are normally used only for internal purposes, but occasionally a buyer or seller will want to use the assigned ad number to find the ad; using the site's search box and typing in the posting number can be an effective way to quickly access the ad in the future.
Find the Ad on Craigslist
Go to Craigslist's homepage and click on the category that corresponds to the ad posting.
Scroll through postings in the ad's category until you have located the ad whose posting number you'd like to access. Alternatively, you can find the posting by typing words that appear within the ad into the "Search Craigslist" box on the left-hand side of Craigslist's homepage. If doing the latter, use the pull-down menu next to the search box to make sure the correct ad category is being searched.
Click on the ad's title to open it once it has been located.
Look in the bottom-left-hand corner of the ad for the term "PostingID" followed by a series of numerals. This is the 10-digit posting number.
Make a note of the posting number for future reference; this is what you'll need to look up the posting in subsequent steps.
Looking up Ads by Posting Number
Go to Craigslist's homepage and locate the "Search Craigslist" box on the left-hand side of the page.
Use the pull-down menu next to the search box to make sure the correct ad category is being searched.
Type in the posting number recorded in Section 1, Step 5. This will allow you to access the ad anytime without having to scroll through multiple postings.
The "Help" section on Craigslist offers a number of alternate ways of finding an ad if looking up the posting number isn't working for you.