Unaffordable and unreliable public transport is cutting off the poorest families in the north of England from crucial job opportunities, a study has found.

Researchers from Sheffield Hallam University and the University of Sheffield, commissioned by the Joseph Rowntree Foundation (JRF), interviewed residents in neighbourhoods across Greater Manchester and Leeds city regions.

Interviewees complained that local transport was expensive, unreliable and slow, making it harder for them to attend job interviews and hold on to paid employment.

The research found that residents were reliant on buses, as running a car and taking the train were too expensive.

Workers complained they were unable to guarantee punctuality because buses were frequently late, meaning they were disregarded by potential employers. The report found that job seekers often turned down jobs because their potential earnings were too low compared with the high transport costs.

The report highlighted the fact that low-skilled manual work in manufacturing or in warehouses was often in locations on the edge of towns and cities that was underserved by public transport.

A 49-year-old interviewee from Leeds expressed frustration at the disconnect: “There’s a place called Sherburn-in-Elmet and they have tons of work, big industrial estate, but there’s no bus service, it’s about 13 miles away. I do not understand why they build a big estate where there’s no transport. If you haven’t got a car you can’t have a job.”

The JRF said the report’s findings undermined advice from the Department for Work and Pensions and Jobcentre Plus that workers should search for roles up to 90 minutes from their homes, as the distance could be simply inaccessible.

A 30-year-old from Dewsbury Moor, in West Yorkshire, spoke of the dwindling help from his Jobcentre Plus: “They do not offer any advice or support with transport issues. Every now and again, an adviser will look up the nearest bus route for you, but don’t look at the practicalities of it.”

Brian Robson, the JRF’s acting head of policy and research, said the government should invest in transport networks within cities not just between them.

“Currently unaffordable and unreliable public transport is holding people back from being able to achieve a better standard of living,” he said. “With more powers being devolved to city and local leaders, now is the time to redesign our transport, housing and economic policies so that everyone can get into work and progress in their careers.”

Ed Ferrari, director of regional economic and social research at Sheffield Hallam University, said: “Buses are the backbone of local public transport in Britain and the key to employment and training opportunities for many. But problems with high fares, poor coordination between different providers and services, and lack of reliability seriously hamper the ability of low-income groups to commute to more distant jobs.

“Fundamental weaknesses in the way that bus services are regulated and subsidised are effectively locking the poorest out of the opportunities within the modern economy. Policymakers in Britain need to see investment in high quality local transport systems as an investment in national productivity and tackling inequality.”

A Department for Transport spokesperson said: “The government is spending more than £13bn through to 2020 to transform transport across the north – the biggest investment any government in history has ever made. We have also given councils extra powers to work in partnership with bus companies to improve the services passengers expect and deserve.

“We recognise that buses are vital in connecting people, homes and businesses, and we provide around £250m every year to support these services up and down the country.”