Great advice, but a couple edits/comments: You don't need $20 if you're only coming through DC for these flights and won't be visiting anytime soon (or just don't want to have to deal with keeping track of the card. The trip from airport to airport should be $3.85 on Friday before 3pm and $2 on the weekend. I believe when you purchase an initial card it charges you $10, $2 of which is for the card and $8 for your fare, which is more than sufficient for these two trips.
Odd-Refrigerator849 t1_ja1iivo wrote
Reply to comment by SluggingAndBussing in Flight layover IAD and DCA...help! by Parking-Steak8032
Great advice, but a couple edits/comments: You don't need $20 if you're only coming through DC for these flights and won't be visiting anytime soon (or just don't want to have to deal with keeping track of the card. The trip from airport to airport should be $3.85 on Friday before 3pm and $2 on the weekend. I believe when you purchase an initial card it charges you $10, $2 of which is for the card and $8 for your fare, which is more than sufficient for these two trips.
You can use the metro's trip planner at https://www.wmata.com/schedules/trip-planner/ or Google Maps is surprisingly accurate.
You can also load your card onto your phone after you purchase it if you install the SmarTrip app if you don't want to keep track of your card.