Trescothick made his announcement just a fortnight after being included in England's provisional 30-man squad for September's inaugural World Twenty20 in South Africa, saying he'd yet to fully overcome the effects of a stress-related illness that has kept him out of international cricket for nearly a year.
Given that the left-handed opener is now 31, his decision has significantly reduced his chances of extending an England career which has so far featured 76 Tests and 123 one-day internationals.
And with England unlikely to pick Trescothick at home until he has proved himself on tour, he now faces at least another 12 months in the international wilderness.
There was little solace on Wednesday on the field for Trescothick, out for 18 in a County Championship match away to Derbyshire.
Trescothick, after play ended at Derby, said of his decision: "It was relatively hard and it would have been a lovely situation to get back in this winter but I knew as the days went on and the way things were progressing that I wasn't quite ready for it yet.
"I've still got aspirations of getting back and I believe I will get back but it's not a simple road and I can only assess it as I play for Somerset."
However, with a packed international programme unlikely to become less congested, the lure of county cricket could grow stronger for Trescothick - who returned home early from his last two England tours, from India in February 2006 and from Sydney last November.
"County cricket has been great fun this year," he said. "It's less stressful and you spend more time at home."
"Every England game I saw on TV I thought I would love to be back there. But then when I thought about it in depth I realised I wasn't ready to go yet."
Trescothick revealed his wife is expecting their second child while England are away but said that wasn't the over-riding reason behind his decision not to tour.
"The baby is due in January. I have looked at that, my family is important to me, but it was more about other factors."
England's chairman of selectors, David Graveney, said: "The selectors have been acutely conscious that it would be counter-productive to try to rush Marcus back into international action before he was ready."
Trescothick has been in fine form for Somerset this season, scoring three hundreds, including a career-best 284 against Northamptonshire, and has been averaging over 70 in first-class cricket.
But he has always been cautious about his international prospects. After being included in the provisional Twenty20 squad on July 11, he said he would "not commit myself before I am as convinced as I can be that I am ready to take on the challenge of international cricket and all that goes with it again".
Trescothick hasn't played for England since being bowled for nought by Shoaib Akhtar during a one-day international against Pakistan on September 5 last year.
Following that match, he made himself unavailable for the Champions Trophy tournament in India but was included for the subsequent Ashes tour only to withdraw before the first Test.
Trescothick has scored more than 10,000 runs in all international cricket including an England record 12 one-day international hundreds.
Although replacement opener Alastair Cook has made a fine start to his Test career, with six hundreds in 19 matches to date, Trescothick has been a notable absentee in the shorter form of the game and especially during England's lacklustre display at the World Cup in the Caribbean earlier this year.
Trescothick will now miss an England winter programme also featuring six Tests and 10 one-day internationals split between Sri Lanka and New Zealand.