It updates in the MLS right away, but it does take longer for the updates to show up on various websites.

Our local MLS is updated within minutes of a new listing or when a change is made.

The MLS updates right away. When you are looking at different websites it really depends on that website and how often it updates.

Tracy,
It looks like you are in Illinois. Our MLS is MLSNI (Multiple Listing Service of Northern Illinois) and it uploads photos, changes, etc. immediately. Have your agent send you a copy of your listing via email through the MLS and you should be able to see the changes.
As others stated, as far as uploading to other sites outside the MLS, it can take a couple of days for it to feed.
Good luck on your home sale!

Hi Tracy,
I'm assuming you're in Illinois and for your pics to upload to various sites will take a couple of days. They immediately go on the mls, but as explained below, they use "feeds" and they can take a little time. For example, on realtor.com, I have posted pics on the mls and some took one day, while others took a few days. Good luck on your sale, the market is picking up!

In the MLS Realcomp in Michigan you can upload pictures instantly, but since other websites take those same photos and manipulate them for their own sites the time for those to be changed is more like 12 to 24 hours. To make sure the best pictures are used in featuring your property make sure your agent has access to Realtor.com and can manually manipulate and download photos onto it directly. That way you can ensure the best and most up to date pics are used to feature your property.

Tracy,
Each MLS is different depending on the company managing it. Our MLS in this area can take up to 12 hours to update sometimes. You can add some time on to that for the listing to push up to the other website. So check with your realtor to follow up and they can in turn check with their administrative people to make sure everything is in.

Larry Story
Coldwell Banker Triad

Typically, the MLS updates almost instantly.... but the websites that the public can view often take anywhere from overnight to 2-3 days.

They take their feeds from the local MLS, but depending on how often they draw the feed, can make the difference. It's rare that it's more frequently than overnight.

It generally takes about 15 minutes to sweep and update.

While I am in Charlotte, NC, I believe all MLS systems update in real time... immediately.