Most weeks, United publishes last-minute weekend deals for travel to/from their hub cities:

• Washington Dulles (IAD)
• Newark (EWR)
• Chicago O’Hare (ORD)
• Houston (IAH)
• Denver (DEN)
• San Francisco (SFO)
• Los Angeles (LAX)

Especially for last-minute travel, these can be fantastic deals, usually starting at $161 roundtrip including tax.  If you have a family emergency or a just-need-to-getaway-emergency, these deals are available almost every week, and are usually published by Monday afternoon for travel on the upcoming weekend.

You can find the deals by visiting United’s website, going to the Deals & Offers menu at the top, and choosing United Specials:

One stipulation is that you must depart after 7 pm on Friday (or anytime on Saturday), and you must return on Monday or Tuesday.  So unfortunately, you can’t return on Sunday with these specials, but for last minute travel, it’s tough to beat!  You won’t find these fares searching on Kayak, Expedia, Orbitz, etc – you have to book them directly with United.