Runner Darren Foy, 40, from Southampton and his wife Sandra and their two children missed the explosions by just 30 minutes after he finished the marathon in three and half hours.
Speaking from the city, the chartered surveyor said:
We were on our way home when we heard something had happened and I was getting messages like 'are you Ok?' which I never get. It's all quite shocking really.
We got home and we looked at the BBC online and saw there had been explosions but we are OK because I finished in three and a half hours and we were on the bus when it happened.
We are staying five miles outside and I'm not intending to go back into the city for a few days.
It's such a soft target. There are hundreds of thousands spectators on the streets and 27,000 runners, so we got off lightly.
More top news
The singer ended speculation over who would perform by saying "the rumors are true" to her 63 million Twitter followers on Friday morning.
There will be lighter winds for all of us than yesterday, although it will still feel cool.
Senior fashion analyst at Mintel Tamara Sender said: "For the first time ever sales of trainers have overtaken high heels."