Reading's U21 continued their 100% record in the Under 21 Premier League Cup tonight on a cold night in Leyland.
It means they are now just two games away from once again reaching the final.
In-form striker Dominic Samuel gave the Royals the lead on 15 minutes, but Bolton equalised before half time through Rob Holding.
With neither team able to get a winner, the game went into extra time.
It took the cup holders just two minutes of extra time to retake the lead through midfielder Aaron Tshibola.
A fine taken goal from Jack Stacey gave Reading breathing space.
Any chance of a Wanderers comeback was effectively ended when Tom Walker was sent off for an off the ball incident involving Craig Tanner.
This was another impressive cup performance from the U21s against a Bolton team which included England international Emile Heskey and Hungary international goalkeeper Adam Bogdan.
Reading: Lincoln, Long, Griffin, Keown (c), Sweeney; Kelly (Cardwell 116), Tshibola (Shaughnessy 105), Stacey, Fosu, Tanner, Cardwell
Subs: Ward, Hyam
Booked: Fosu (foul 67), Tshibola (foul 99)
Bolton: Bogdan, Holding, Sellers, Maher, Taylor, Finney, Kamara (Woolery HT), Lester, Odelusi (Ball 105), Heskey (Thomas 65), Walker
Subs: Fitzsimmons, Matthews
Sent off: Walker (foul 107)