You can find a log-in link at the bottom of most SmugMug pages.
On SmugMug's homepage, you'll find the log-in option in the top-right corner of the navigation bar.
Am I logged in?
If you're already logged in, you'll see this in the global navigation bar at the top of your site:

If you only see the words Upload and My Site, then you've logged in with an assistant password. If you're logged in as an assistant, you won't see any of the business options in the Site Settings; you'll only see Stats and Comments.
I can't log in!
Forgot your password? No worries. Click here to request a password reset. (If no email arrives, check your bulk and spam/junk mail folders. It might have gotten caught by your email program's filters.)
If you're already logged in, you'll first need to log out before requesting a password reset.
If neither your password nor your email are the issue, then cookies might be causing the problem.
Important: Power, Portfolio, and Pro account subscribers who use custom domains should log in and log out using your email and password from www.smugmug.com and not from the custom domain.
Looking for your print order?
If you'd like to view a print order you placed with SmugMug, you need to go straight to the order status page (you can find the link in the order-confirmation email) rather than using the log-in link. If you do have a SmugMug account and placed an order while logged in, you may also go to your Site Settings > Site > Receipts tab to see any orders you've placed. Click on the order you want to view the details.