Annie was born in Springhead, Saddleworth, in the West Riding of Yorkshire (part of the Borough of Oldham), on 13 September 1879, the 4th daughter (of 12 children) of Nelson Horatio Kenney (1849-1912) and Anne Wood (1852-1905); the family was poor and working class, and Kenney started part-time work in a local cotton mill at the age of 10, as well as attending school; turning full-time at 13 – which involved 12-hour shifts from 6 in the morning to 6 in the evening. She was employed as a "tenter", a weaver's assistant, part of her job being to fit the bobbins and to attend to the strands of fleece when they broke; during one such operation, one of her fingers was ripped off by a spinning bobbin. She remained at the mill for 15 years, becoming involved in trade-union activities, furthering her education through self-study, and promoting the study of literature amongst her work colleagues – inspired by Robert Blatchford's publication, The Clarion; she was also a regular church attender .
Kenney became actively involved in the Women's Social and Political Union (WSPU) after hearing Christabel Pankhurst speak at the Oldham Clarion Vocal Club in 1905.
During a Liberal rally at the Free Trade Hall, Manchester, in October 1905, Kenney and Christabel Pankhurst interrupted a political meeting to ask Churchill and Sir Edward Grey if they believed women should have the right to vote. Neither man replied. The two women got out a banner declaring "Votes for Women", and shouted at the two politicians to answer their questions. Kenney and Pankhurst were thrown out of the meeting and arrested for causing an obstruction and a technical assault on a police officer. Annie Kenney was imprisoned for three days for her part in the protest, and 13 times in total.
Emmeline Pankhurst later wrote in her autobiography that "this was the beginning of a campaign the like of which was never known in England, or for that matter in any other country ... we interrupted a great many meetings... and we were violently thrown out and insulted. Often we were painfully bruised and hurt."
Kenney was the only working class woman to become part of the senior hierarchy of the WSPU, becoming deputy in 1912, unusual in such a middle class organisation.
Kenney was involved in other militant acts and underwent force-feeding many times, but was always determined to confront the authorities and highlight the injustice of the Cat and Mouse Act. On one occasion in January 1914 she had just been released from prison and was very weak, but it was reported in The Times that at a meeting chaired by Norah Dacre Fox the WSPU general secretary at the Knightsbridge Town Hall:
Miss Kenney was conveyed to the meeting in a horse ambulance; and she was borne into the meeting on a stretcher, which was raised to the platform and placed on two chairs. She raised her right hand and fluttered a handkerchief and, covered with blankets, lay motionless watching the audience. Later, her licence under the "Cat and Mouse" Act was offered for sale. Mrs Dacre Fox stated that an offer of £15 had already been received for it, and the next was one of £20, then £25 was bid, and at this price it was sold. Soon afterwards Miss Kenney was taken back to the ambulance. Detectives were present, but no attempt was made to rearrest Miss Kenney, whose licence had expired.
At the outbreak of World War I in 1914, Emmeline Pankhurst called an end to suffragette militancy and urged the women to become actively involved in war work by taking on jobs that had traditionally been regarded as in the male preserve, given that those men were now absent at the front. This was set in train through the pages of The Suffragette, relaunched on 16 April 1915 with the slogan that it was 'a thousand times more the duty of the militant Suffragettes to fight the Kaiser for the sake of liberty than it was to fight anti-Suffrage Governments'. As part of this during the autumn of 1915 Kenney accompanied Emmeline Pankhurst, Flora Drummond, Norah Dacre Fox (later known as Norah Elam) and Grace Roe to South Wales, the Midlands and Clydeside on a 'recruiting' and lecture tour to encourage trade unions to support war work. She took her message as far afield as France and the United States, but eventually married James Taylor (1893-1977) and settled in Letchworth, Hertfordshire, after women (over 30) won the vote in 1918. A son, Warwick Kenney Taylor, was born in 1921.
She died of diabetes at the Lister Hospital in Hitchin on 9 July 1953 aged 73. Her funeral was conducted according to the rites of the Rosicrucians and her ashes were scattered by her family on Saddleworth Moor.
In 1999, Oldham Council put up a blue plaque in her honour at Leesbrook Mill in Lees near Oldham where she started work in 1892.