When nearly a fifth of the 6,000plus workforce has been on the same company’s payroll for more than 15 years, you start to wonder what the firm is doing right. At American Express (Amex) the clear fortes are great managers, close teams, relatively low stress levels and scope for development, the results of this year’s employee survey reveals.

High proportions of staff have also been with the travel and financial services firm for between five and 10 years — 1,688 of them to be precise — and 633 people have been with the company for 10 to 15 years. And it isn’t a case of tired old-timers with no ambition to move upwards clocking up such long tenure. Staff stay because they are given the stimuli and career prospects to keep them interested, as well as a good set of benefits to keep them comfortable.

They say their job is good for their own growth (rating this question 75% positive) and at 68%, the score for happiness with the balance between work and home life is the third best result for this question among the 20 Best Big Companies to Work For.

Sharon Pannett, director of business travel accounts and card financial processing, has worked at Amex for 23 years. Her husband, now retired, had 33 years’ service at the company. She explains why she doesn’t have itchy feet: “I joined as a temp doing under and overpayments and I’ve been able to develop to director level. You’re constantly being given opportunities.”

Pannett is one of a breed thought to be extinct — someone with a job for life — as she explains: “I’d like to see my career end here. I remember my first day, I was 17 years old walking across the forecourt feeling really proud to work for Amex, and I’ve never lost that.” She is not alone in benefiting from the company’s propensity to promote from within. The firm estimates that of 636 senior managers in the UK arm of the business, about 85% are internal appointments.

Martin Jackson, team manager in travellers’ cheque cards, says he joined Amex because of its people-centric culture. “It’s not just a one-off hit. It’s a proper culture,” he says. He likes the fact that employees do not stagnate. “I joined Amex in risk, but you’re encouraged to move around and network. I can choose a mentor from a different area. The theory is that the skills are transferable, it makes sense,” he says.

“There is genuine empowerment. Sometimes managers can tell you that it’s your responsibility, but they still look over your shoulder. I see it as my business. As soon as I started, my manager was asking me what I thought about things, he wanted to know my opinion,” he says.

His colleagues agree: they feel their managers talk openly and honestly with them (78%), trust their judgment (79%), care about them as an individual (75%), share important information with them (73%) and don’t do a lot of telling without much listening, earning this question a 72% positive score — all top four results.

The company employs innovative practices to help facilitate communication. So-called “skip level” reviews involve quarterly team meetings that skip the immediate line manager out of the process. Skip-skip level reviews also take place.

About 500 employees took part in charitable activities during work time last year, in line with a core company value of “being a good citizen in the communities in which we work”. Staff feel supported in their efforts to help good causes outside the business, giving this question a 76% positive score, the fifth highest in the list.

On a global scale, Amex joined other business leaders and Bono at last year’s World Economic Forum in Davos to launch Product Red — a union of branded products aimed at driving commerce to help people affected by HIV and Aids in Africa. The Red American Express card gives a minimum 1% of spending to the Global Fund. While staff responded to the question asking whether their company’s support of worthy causes was driven by a desire for good publicity with just a 52% positive score, this was still good enough to rank Amex ninth on this point.

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