The incident has resulted in a number of a cancellations and delays with disruption expected until at least 9.30am.
ScotRail confirmed the line has reopened after a safety inspection however there will be a knock-on effect to services, including the 8.59am Tweedbank to Edinburgh which is cancelled.
A ticket acceptance is in place with Borders Buses between Edinburgh Waverley, Eskbank, Newtongrange, Gorebridge, Stow and Galashiels on bus route X95.
Passengers can also use their tickets on Lothian buses between Edinburgh, Brunstane, Newcraighill, Shawfair, Eskbank, Newtongrange and Gorebridge.
A spokesperson for ScotRail said: “Following a road vehicle colliding with a bridge earlier today between Newcraighall and Brunstane the line is now open. Disruption is expected until 09:30 28/11.
“Train services between Edinburgh and Tweedbank are returning to normal but some services may still be cancelled, delayed or revised.”
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