Here are reputable websites and services that will notify you when award seats become available — with a short note on what each does best and whether it’s free or paid.

• ExpertFlyer — industry-standard flight & award alerts. Create “flight” or “award” availability alerts for specific flight segments; very granular and fast (most features require a paid subscription). (BrandRadar.org)

• Roame — award-availability search + alerts. Lets you monitor routes/regions, cabins and date ranges and sends email/in‑app alerts when saver award seats appear (many alert features are part of paid tiers). Good for flexible searches (region → region). (help.Roame.travel)

• SeatSpy — focused reward-seat searches and alerts (popular with Avios/BA users). Useful for monitoring specific routes/dates for British Airways and some partners; has free tier but best features require subscription. (BrandRadar.org)

• AwardFares — multi-program award search with automated alerts. Aggregates availability across programs and provides timeline/calendar views plus email/push alerts when seats open (paid plans for frequent checks). (en.wikipedia.org)

• Point.Me — broad, real‑time award search engine; offers “subscribe to search” / fare-alert features and booking help. Strong for finding complex partner routings and hidden options; mostly a paid service. (Point.Me)

• Seats.aero / Seats.aero-like tools — fast reward search + alert options for premium cabins on many carriers; typically subscription-based and used by people hunting premium award space. (BrandRadar.org)

• PointsYeah — lower-cost / freemium alternative that supports live searches and award‑price alerts for some routes. Good if you want a cheaper multi-program monitor. (helpmebuildcredit.com)

• MaxMyPoint — hotel award availability alerts (if you also want hotel award notifications rather than flights). Paid for best features. (blog.tripplus.cc)

Other useful options

• Travel blogs / curated newsletters (e.g., Straight to the Points, Frequent Miler, The Points Guy) — they send curated premium-cabin award alerts and deal roundups; good for “big” opportunities but not for monitoring a specific route/date. (straighttothepoints.co)

Quick suggestions on which to try

• If you want the most granular, airline-level alerting: start with ExpertFlyer. (BrandRadar.org)
• If you prefer fast region-to-region monitoring and flexible searches: try Roame. (help.Roame.travel)
• If you focus on Avios/BA routes: SeatSpy is a good, specialized choice. (BrandRadar.org)
• If you want a broad multi-program search + booking help: test Point.Me or AwardFares. (Point.Me)

If you want, tell me the route(s), cabin, and date-range you care about and I’ll recommend the single best service (or combination) for monitoring that specific search.