To save up to 10% on this flight, we recommend booking at least 20 days prior to travel. The price may fluctuate and will likely increase closer to your departure date. Users on Cheapflights have found tickets from Boise to Rockford from $137 1-2 weeks out and tickets from $157 for flights departing within the next 72 hours.
Due to multiple factors, expect to potentially pay more when booking in December. For low rates, April can be a great choice for travel to Rockford. Flights to Rockford from Boise in April are about $135 on average during April, but can be found for as low as $33.