At the age of 19 (in 1812), he began writing for newspapers and soon gained attention for the boldness and liberality of his opinions and for the superiority of his style amid what Macaulay, when speaking of him, called the "rant and twaddle" of the daily and weekly press.
This regime led to his health breaking down again, but he continued to write regularly for newspapers and reviews and make a reasonable living.
From 1820 to 1830, Fonblanque was employed on the staff of The Times and the Morning Chronicle, whilst contributing to the Examiner to the London Magazine and the Westminster Review.
In 1826, Fonblanque became political commentator for The Examiner, a weekly newspaper founded by Leigh and John Hunt in 1808.
When it was proposed that supporters of the paper should facilitate a reduction in its price by paying their subscriptions ten years in advance, they were joined by Edward Bulwer-Lytton and by Benjamin Disraeli, who was then flirting with radicalism.
Journalism before Fonblanque's day was seen as a somewhat discreditable profession: men of culture were shy of entering it, lest they be confused with the ruder combatants fighting for public notice.
Fonblanque, with his strong and earnest political convictions and exceptional literary ability, did not hesitate to choose the field as one where a politician and a man of letters might usefully and honourably put forth his gifts.