We are a family of 4 who will be traveling from Washington DC to Frankfurt then on to Prague via Lufthansa air. we will all have a carry on and a personal item. I am worried about customs coming into Frankfort as our connecting flight is only 1 hour a 20 minutes after we land. Is this enough time, and is there anything we can do to expedite the process?

Welcome to Fodors. You go through Border Control (Immigration) at FRA and Customs at Prague. There is no way to expedite Immigration - it is what it is. If you land on time 80 minutes should be fine. But if these are on the same booking you are protected and if you miss the connection they will put you on the next available flight. (If they are separate tickets all bets are off)

It is on the same ticket so looks like we will be good!!! thank you

We had a tight connection in FRA one time when our incoming plane was late. Lufthansa reps met us at the arrival gate and escorted us past the long line at passport control to a special booth. Then we skipped a security line and they did a pat down and wand scan before getting us to the next plane. A bit unnerving but the fastest transfer we've ever had.

Over many years transiting through Frankfurt I've made some 45min connections, and missed some 2hr connections. Those times are actual, not scheduled. The biggest variable is whether your incoming flight arrives on time.

I've had the same experience as greytop. If you're connection is tight (as in <45min) then talk to a LH agent as you deplane and they may be able to help you out. At least they can notify the next flight you are enroute.

I would have no concern booking an 80min layover. You can give yourself more info by knowing when the next flight to Prague leaves just in case.