The value of a 1935 A US $20 bill depends on its condition and rarity. In general, an average circulated 1935 A $20 bill can be worth around $80 to $100. However, the value can increase for well-preserved uncirculated notes or rare varieties. It's recommended to get the note professionally graded by a reputable third-party grading service like the Professional Coin Grading Service (PCGS) or the Numismatic Guaranty Corporation (NGC) to obtain an accurate valuation.