Boss John Gregory admitted his side got what they deserved after producing another underwhelming performance against one of League One's strugglers.
Reds saw their three-match winning run come to an end as Jimmy Spencer's first half strike earned Notts County a precious win in their battle to avoid the drop.
Crawley pushed for an equaliser in the second half with Jamie Proctor having a shot cleared off the line and Bartosz Bialkowski pulling off a string of fine saves but Gregory said it was too little too late.
The Reds boss said: "We can't afford to not perform. The first 45 minutes was very similar to the Oldham game when we didn't turn up and then suddenly got going in the second half.
"I'm very disappointeed but that has been the story of our season. We rolled up our sleeves and really had a go at it in the second half but they defended with their lives, as you would expect.
"Their goalkeeper made a couple of brilliant saves and we had enough chances to get a point which would have been all we deserved on the day.
"But I shouldn't be too hard on them because this was our fourth game in nine days and our 18th in 58 days which is incredible really."
County boss Shaun Derry was delighted with the result which boosted the Magpies' hopes of survival.
Derry said: "It is a huge win. We rode our luck at times but I don't care as we got the three points and that is all that matters."