Six out of ten Tube drivers went to work on Tuesday despite the industrial action by the RMT union.
The 60% figure was slightly up on the April walkouts when it was 57%.
More than half of Tube drivers are members of the Aslef train drivers’ union which is not striking and has firmly backed a proposed four-day week.
However, it is understood that more RMT drivers turned up to work on Tuesday than in the April walkouts in a dispute over the new four-day week for drivers who earn around £74,000-a-year.
Transport for London (TfL) said the 6am turnout of drivers allowed it to run around half of Tube services in the morning peak.
Just two drivers on the Jubilee Line did not turn up to work which meant that its service was close to normal early on Tuesday.
RMT chiefs had “instructed” drivers not to go to work on the two strike days this week.
A TfL spokesperson said: “We are sorry that today (Tuesday) has been difficult for customers and for London’s business, but are pleased that we have been able to offer service on almost every Tube line today despite the strike action taken by the RMT, including the Jubilee Line operating a normal service.
“Only a handful of drivers had stayed away from work on the Jubilee Line, and overall around 60 per cent of drivers came to work which is more than in April’s strike action.
“We continue to urge the RMT to work with us to resolve their questions on the proposed four-day week and to suspend any future action while that work is completed.”
However, hopes that the strike on Thursday may be called off have been dashed after a TfL boss said the union had made clear it would be pressing ahead with the second day of its industrial action this week.
An RMT spokesperson said: “Our strike has been strongly supported by RMT members with well attended picket lines at Tube stations and depots.
“We are available at any time for talks to try to find a negotiated settlement and expect to meet the employer next week."
In a read-out of the impact of the walkout on Tuesday, TfL said that Oyster and contactless tap data up to 10am showed:
* London Underground: down 43% compared to the equivalent day last year.
* Elizabeth Line: up 17%
* London Overground: up 9%
* Bus boarding taps up 5%
Across all transport modes, 1,796,826 unique cards (Oyster and contactless cards) were recorded on the network, around 86 per cent of the equivalent day last year.
TfL stressed that the data showed the vast majority of Londoners were still travelling on the network to get to work, school or for other journeys despite the strike.
Services ran on most Tube lines, other than the closures planned on the Circle, and Waterloo and City lines.
The RMT has rejected the proposed reforms, branding them a “fake” four-day week and raising concerns over fatigue of drivers who may be told their shifts at short notice.
But the changes have been accepted by Aslef which has hailed them as offering drivers the best working conditions on the mainline rail network.
TfL has stressed that the four-day week is voluntary and no driver will be forced to accept it.
