But what is the most common reason for strikes? We investigate
There have been 28 Tube strikes since 2008 spanning 65 days, according to information obtained by LondonLovesBusiness.
The data provided by Transport for London under the Freedom of Information Act, showed 2014 was the biggest year for strikes by London Underground staff.
Last year, there were eight separate tube strikes affecting 30 days of the year – 16 of these related to Power Control Room Operations staff.
The most common reasons given for strikes were the dismissal of an employee and a breakdown in industrial relations, with seven strikes each called for these reasons in the last seven years.
So far in 2015, there have been three separate strikes that have affected six days overall. The most common reason this year was the introduction of the Night Tube and how it related to staff pay and conditions.
This week, Piccadilly Line workers voted in favour of a strike over TfL’s “bullying, harrassment and intimidation”. About 70% of affected RMT members backed industrial action, but a date for the strike has not been set.
TfL said: “We encourage unions to engage in negotiations to resolve any disputes that may result in industrial action. When it has not been possible to prevent industrial action, we roll out well prepared operational plans to ensure that services operate safely at all times under busier than normal conditions.
“We deploy additional staff (including managers and revenue control staff) to assist local staff and provide advice to customers. We issue communications to inform customers that services will be busier than usual. Extra bus and river services are operated to help people get around, and we continue to update the TfL website as well as our other social media outlets which we encourage our customers to check frequently to see how their journeys could be affected.”
Sales during strikes
Meanwhile, research by data software company Applied Predictive Technologies found Tube strikes this summer had a detrimental effect on retail and restaurant sales in central London.
Sales shifted to the suburbs on the main day of Tube strikes, 6 August, compared to the same weekday the year before.