The Factories Act 1847 (10 & 11 Vict. c. 29), also known as the Ten Hours Act was an act of the Parliament of the United Kingdom which restricted the working hours of women and young persons (13–18) in textile mills to 10 hours per day. The practicalities of running a textile mill were such that the act should have effectively set the same limit on the working hours of adult male mill-workers.

Defective drafting meant that a subsequent Factory Act in 1850 imposing tighter restrictions on the hours within which women and young persons could work was needed to bring this about.^{[clarification needed]} The 1847 act was the culmination of a campaign lasting almost fifteen years to bring in a 'Ten Hours Bill'; a great Radical cause of the period. Prominent advocates and people involved with the act include Richard Oastler, Lord Ashley (he was not an MP in the session when the act was passed), John Doherty and sympathetic mill-owners such as John Fielden. The fiercest opponents of all ten-hour bills were the 'free trade' Liberals such as John Bright; the economic doctrines that led them to object to artificial tariff barriers also led them to object to government restricting the terms on which a man might sell his labour, and to extend that objection to women and young peoples. Karl Marx, speaking at the International Workingmen's Association meeting in November 1864 said of it "This struggle about the legal restriction of the hours of labour raged more fiercely since; apart from avarice, it told indeed upon the great contest between the blind rule of the supply and demand laws which form the political economy of the middle class, a social production subjected to a foreseeing social control which forms the political economy of the working class. Hence the Ten Hours’ Bill was not only a great practical success; it was the victory of a principle; it was the first time that in broad daylight the political economy of the middle class succumbed ignominiously, ludicrously, before the political economy of the working class".

The act stipulated that as of 1 July 1847, women and children between the ages of 13 and 18 could work only 63 hours per week. The Bill further stipulated that as of 1  May 1848, women and children 13–18 could work only 58  hours per week, the equivalent of 10 hours per day.

The Labour of Children, etc., in Factories Act 1833 (3 & 4 Will. 4. c. 103) had specified an eight-hour working day for children (aged nine to thirteen) and a twelve-hour day for 'young persons' (fourteen to eighteen) but it had proved difficult to enforce, and its attempts to ensure the education of mill-children had failed. Under the Whig government of Lord Melbourne, Fox Maule had repeatedly produced draft factory bills which were to replace the 1833 act and better address these issues, but the Whigs had never found the political will and the parliamentary time to get a new Factory Act passed. Maule's later draft bills had proposed reducing the working hours for children to allow better access to better education but had otherwise left hours of work unchanged. A short-time movement in the textile districts sought a ten-hour day for all millworkers, which it believed would be effectively secured by reducing the working hours for young persons: Lord Ashley supported their cause.

The Whigs were defeated in the 1841 general election, and Sir Robert Peel formed a Conservative government. Ashley let it be known that he had declined office under Peel because Peel would not commit himself not to oppose a ten-hour bill; Ashley, therefore, wished to retain freedom of action on factory issues. In February 1842, Peel indicated definite opposition to a ten-hour bill, and Sir James Graham, Peel's Home Secretary, declared his intention to proceed with a bill prepared by Fox Maule, but with some alterations. In response to the findings of a royal commission, Ashley saw through Parliament the Mines and Collieries Act 1842 (5 & 6 Vict. c. 99) banning the employment of women and children underground; the measure was welcomed by both front benches, with Graham assuring Ashley "that her Majesty's Government would render him every assistance in carrying on the measure". In July, it was announced that the Government did not intend any modification to the Factory Act in that session.

In 1843, Ashley initiated a debate on "the best means of diffusing the benefits and blessings of a moral and religious education among the working classes..." The Royal Commission had investigated not only the working hours and conditions of the children but also their moral state. It had found much of concern in their habits and language, but the greatest concern was that "the means of secular and religious instruction.. are so grievously defective, that, in all the districts, great numbers of Children and Young Persons are growing up without any religious, moral, or intellectual training; nothing being done to form them to habits of order, sobriety, honesty, and forethought, or even to restrain them from vice and crime."

The State had no responsibility for the provision of education, and the working classes themselves had neither the capital nor the income to set up and support schools giving an effective education to their children. Through the Privy Council, government money (the Education Grant) was available to cover up to one-third (in principle; in hard cases up to a half) of the cost of setting up an 'efficient' school (one giving an effective education) where none existed. Since the repeal of the Test and Corporation Acts, many of the grievances of the Dissenters had been addressed, until the Whig government felt itself politically unable to go further because of the increasing concern (and resentment) of Anglicans at the systematic erosion of the Church of England's status as the national church (indeed Graham had left the Whig government to join the Conservatives because of his objections on this point). Church and organised Dissent regarded each other not as a colleague, but at best as a competitor, and too often as an opponent (and one which had been unduly favoured by the government). Consequently, two charities existed to assist the formation of efficient schools; the British and Foreign School Society for the Education of the Labouring and Manufacturing Classes of Society of Every Religious Persuasion was non-denominational and hence was favoured by Dissenters. Its implications for the Established Church were noted by an anonymous contemporary American commentator "Without swerving a hair's breadth from"( their declared principles) "they would by their mere negative influence, utterly subvert (and that at no distant day, if counteracting influences were not vigorously employed,) the church establishment, as such; and make Episcopacy in England what it is in this country, one of some dozen sects, all depending for their influence, and for the extent to which their doctrines and usages shall be received, upon the judgement, conscience, education, or caprice of their fellow men". Such an outcome would not be unwelcome to Dissenters; to avert it, churchmen had founded a rival organisation: the exclusively Anglican National Society for Promoting the Education of the Poor in the Principles of the Established Church in England and Wales. Its aim was that "the National Religion should be made the foundation of National Education and should be the first and chief thing taught to the poor, according to the excellent Liturgy and Catechism provided by our Church."

Since the Factory Act required factory children to attend school, the factory inspectorate had been drawn into taking a view on the quality of schooling the children were getting. The "British" and "National" schools they considered acceptable and a very few manufacturers had set up their own factory schools of equivalent quality; but there were populous manufacturing districts (Oldham and Ashton-under-Lyne were the examples given) where there were few or no efficient schools. Below these schools, there could be, for Dissenters, day schools associated with their place of worship – although often described in their locality as 'British' schools they were not formally so and in most cases, the quality of education given was in no way comparable. (The organisation and discipline of the Established Church prevented any similar phenomenon of 'unofficial' National schools.) Other than this the quality of education was generally poor.