Here’s a pair of outstanding airfare deals to act on today! Both of the offers do not have a ticket-by date which indicates they could vanish in a matter of hours.

$74 one-way to New York City-LaGuardia: This American Airlines exclusive is valid only on Tuesdays and Wednesdays, but this awesome rate is valid on trips completed on or before Jan. 29, 2014. The big bonus: there are no Labor Day, Thanksgiving or New Years’ blackout dates. Here are the dates to avoid: March 22-24, 28-31; June 13-17, 20-24; June 27-July 1; July 4, 6-8, 11-15, 18-22, 25-29 and Aug. 1-5, 8-12. American operates a number of daily, nonstop flights to NYC.

$175 one-way to Toronto, Ontario, Canada: A United Airlines exclusive, this rate is valid on any day of the week (based on sale seat availability) through Jan. 29, 2014. To qualify, give a 21-day or more advance notice of travel. Blackout dates to not apply. United serves Toronto with nonstop service from Atlanta (Jazz), but this special deal is only valid on connection service via Chicago, Newark or Washington, DC. Compare this rate to $275 charged by other carriers.

Sale airfares are always subject to change. Every seat on every flight is not offered at the lowest rate. Since only a limited supply of seats is available, act quickly to make your purchase.

I recommend starting the search for available seats at Kayak.com vs. calling an airline directly. You can also search for the sale at travel websites such as Expedia, Orbitz or Travelocity, etc. Airlines can discontinue or pull a sale price without notice when the offer does not have a “ticket-by” date or when the offer is deemed “sold out.”

Clara Bosonetto is a retired travel consultant.