Coroner Elizabeth Pygott said it was the only possible conclusion after hearing details of the death of Tommy Hollis, in west London.
She added the verdict would not bar prosecution or civil proceedings after it was revealed a metal support was cut by a McNicholas workmen before the lamp post fell.
Tommy Hollis died after being hit in Chiswick on February 23 2010.
Workwe Kelvin Elmore had cut the metal support plate not realising what it was, the three-day inquest heard.
The BBC reported that after hearing all the evidence, Ms Pygott said: “The only conclusion I am, in fact, going to leave to you is that of accidental death.
“The issue of statutory liability for health and safety matters is not for this court and I do not consider that there is any evidence of a gross error that could give rise to any other conclusion.
“But I should add, for your information, that the fact of an accidental conclusion is not a bar to any prosecution or civil proceedings. It is simply a conclusion limited to this court.”
The steel plate connected to the lamppost, outside Chiswick Town Hall, was exposed after a trench was dug during a road widening scheme.
Elmore, who worked for construction firm McNicholas which was responsible for moving Virgin Media cables as part of the council project, tried to remove the metal structure thinking it was part of an old tramline.
The inquest heard he was “utterly devastated” to learn of Tommy’s death.
Elmore was found guilty of gross misconduct by his company and given a written warning. He is still employed by McNicholas.
His colleague Chris Odd said there had been a sense of “urgency” to complete the work, after direction from Hounslow Borough Council.
The inquest heard the council’s head of transport emailed Aecom, in charge of designing the new road layout, to point out the work needed to be done promptly as the general election was approaching.
The message was sent on February 18, the day Elmore cut into the steel plate, which was just 18 inches away from the lamppost.
The Health and Safety Executive is currently investigating the incident.
