The cheapest month to fly from Philadelphia to Bilbao is November, with fares from €159. The most expensive period is August, when prices can reach €318+ — a difference of €159 per ticket. Booking on a Saturday and travelling off-peak can save you significantly on the 5,834 km PHL–BIO sector.
| Month | From price | vs cheapest | Verdict |
|---|---|---|---|
| January | €169 | +€10 | Best value |
| February | €179 | +€20 | Good value |
| March | €199 | +€40 | Good value |
| April | €228 | +€69 | Average |
| May | €218 | +€59 | Average |
| June | €258 | +€99 | Average |
| July | €308 | +€149 | Expensive |
| August | €318 | +€159 | Expensive |
| September | €208 | +€49 | Average |
| October | €189 | +€30 | Good value |
| November | €159 | Cheapest | Best value |
| December | €248 | +€89 | Average |
On the Philadelphia–Bilbao route, Saturdays are typically the cheapest day to fly, while Fridays are most expensive. Mid-week departures (Tuesday, Wednesday) save an average of 15–25% compared to weekend travel.
