The Office for National Statistics said there were 3.5 million such households in the UK between April and June this year, about 17.1% of all households including a working age adult.
This was down from 3.7 million, or 17.9%, a year earlier.
The highest percentage of workless households was in north-east England.
Some 23% of households including a working age adult were workless in the region. The lowest was in south-east England, where 13% of households were in this category.
Workless households are defined as homes where no-one aged from 16 to 64 is in employment. This could be because they are looking for work, or they have chosen not to work, or they are unable to work.
People may choose not to work because of family commitments, early retirement or study. They may be unable to work because of sickness or disability.
The data shows that the number of workless households in the UK dropped by 182,000 over the year.
This means that 4.9 million people aged 16 to 64 lived in workless households. The ONS said this was the first time the figure had dropped below five million since 2008.
Some 14% of all children in the UK, or 1.6 million, were living in these households. About two-thirds of them were in single-parent households.
Children's charities - Barnardo's and The Children's Society - said they welcomed the fact that the number of children living in workless households was falling.
However, a move into work did not necessarily mean a move out of poverty, they argued.
They said it was imperative for the government to reduce childcare costs for families on low incomes.
The proportion of workless households was at its highest in 1996, when comparable records began, when it stood at 20.9% in the UK. This fell steadily to 17.3% in 2006 before rising to 19.2% in 2010. It has fallen relatively sharply in the past three years.
In 2013, there were 297,000 households in which no adult has ever worked, down 43,000 on the previous year. If student households are excluded, this figure drops to 224,000.
Mark Hoban, the Minister for Employment, said: "Helping people off benefits and into work is one of this government's top priorities, so it is good news that the number of workless households has fallen by more than 425,000 since the coalition took office.
"By reforming the welfare system to ensure that people are better off in work than on benefits, and through schemes such as the Work Programme and Youth Contract we are giving people the support they need to get a job and fulfil their aspirations of looking after themselves and their families."
Stephen Timms, Labour's shadow employment minister, said: "Any fall in worklessness is welcome, but the truth is Britain's unemployment crisis is far from over.
"Underemployment is at record highs, long-term unemployment is at its highest level for 17 years, the number of young people out of work is edging back towards a million, and millions are working harder for less. It is becoming harder and harder for millions to make ends meet."
The proportion of UK households where no adult aged 16 to 64 is in work is at its lowest since comparable records began in 1996, official figures show.