South Western Railway (SWR) employees began 27 days of strike action on Monday 2 December, when publicans are usually readying themselves for weeks of extra trade.
Services between London Waterloo and parts of the south-west have been impacted, including suburban commuter lines and others running to the coast.
The industrial action means hundreds of services are being cancelled each day and a revised timetable is in operation with services ending earlier than usual at around 11pm.
UKHospitality chief executive Kate Nicholls said pubs would feel an impact as the earlier end times have made it harder for pub staff to get around later at night as well as customers.
She said: “Many employees in our sector in London rely on reliable public transport running late into the night and earlier into the morning. If those trains are not running then some team members may not be able to get home conveniently and may even need to turn down the offer of work.
“This is all happening at the busiest time of the year for hospitality, when many pubs, bars and restaurants are full of people going out for Christmas. Businesses are going to feel the impact of customers and staff members cannot travel.”
John McElhinney runs a number of pubs near Waterloo station and he said he was worried about the impact of the strikes should they continue.
He said general trade was finishing a lot earlier than normal with a significant downturn in sales from about 8pm.
He said: “Our pubs are a lot quieter towards the end of the night.”
There has been a healthy up-turn in trade at his King’s Arms site – a haven for commuters – which has not continued at the same rate as before strike action started.
McElhinney added: “A lot of the talk and the opinion is that people will go out for Christmas perhaps start earlier and finish earlier if it continues as it is.
“So far, we have been lucky enough that our customers are pretty loyal and quite a lot of our Christmas bookings will be from businesses not too far away from us.”
Some of the pub’s regulars have also been working from home to avoid delayed or overcrowded trains.
See what happens
McElhinney said it remains to be seen how much this long period of strikes will impact business at this time of year but, previously, one-off days of action has attracted new faces into his pubs.
He explained: “Sometimes you see a significant downturn when there are train or Tube strikes but, if it’s a one-off strike, sometimes we have people so frustrated that they actually come in for a pint.”
The operator added: “Thursdays and Fridays are feeling like Mondays and Tuesdays.
“It is a concern in terms of our budget and what we are expecting. We just have to see what happens.
“As far as our managers and team are concerned, we're just keeping them updated with what's happening with the strike.
“For our own budget's sake, we try to manage staffing levels as appropriately and we just hope that an adequate solution [to the dispute] is found.”