Rail unions have arranged two separate strikes – the first on Wednesday, July 27, and the second on Saturday, July 30.
The Wednesday strike, will be a repeat of strikes last month, where no trains will be operating on the county's lines, from Aberystwyth through to Newtown, Welshpool, Shrewsbury, Telford, Cosford and Shifnal, or towards Craven Arms or Crewe from Shrewsbury.
Both West Midlands Railways and Transport for Wales will be affected by the strike from the National Union of Rail, Maritime, and Transport Workers (RMT) – which takes place the day before the start of the Commonwealth Games in Birmingham.
The second strike, on Saturday, which has been called by train drivers' union ASLEF, does not affect Transport for Wales.
West Midlands Railways, which is affected by the action said it was awaiting full confirmation but warned of "a significantly reduced service" for the day.
Transport for Wales said it will be operating a full timetable for the day, but said "services are likely be impacted by strike action at other train operating companies".
It added that the situation could lead to short-notice cancellations and changes.
A spokesman said: "TfW services from Shrewsbury to Birmingham are expected to be very busy with the Commonwealth Games taking place.
"Passengers are advised not to travel unless necessary."
Transport for Wales has also warned of disruption either side of both strike days, with the knock-on impact of the industrial action likely to have a continuing effect on the rail network.
A spokesman said: "Due to the shift patterns of Network Rail’s signallers and the significant challenges moving trains and crew to operate between strike days there is likely to be disruption.
"Customers are urged to check their journey before they travel. Online journey planners will be updated between two and four days before the first strike day.
Transport for Wales said people with existing non-season tickets valid for travel on Wednesday, July 27, and Saturday, July 30, can use them anytime between Tuesday, July 26, and Tuesday, August 2.
Alternatively people can claim a full refund, with no admin fee charged.
Season ticket holders can apply for compensation via Delay Repay.
Sales of advance tickets for the strike dates have been suspended by Transport for Wales in order to cut down on the number of people disrupted.
Mick Whelan, general secretary at Aslef, said the strike had been confirmed because the pay offer for drivers did not keep pace with the rising cost of living.
He said: "We don’t want to go on strike – strikes are the result of a failure of negotiation – and this union, since I was elected GS in 2011, has only ever been on strike, until this year, for a handful of days.
"We don’t want to inconvenience passengers – not least because our friends and families use public transport, too, and we believe in building trust in the railways in Britain – and we don’t want to lose money by going on strike.
"But we’ve been forced into this position by the train companies, driven by the Tory government. The drivers at the companies where we are striking have had a real terms pay cut over the last three years – since April 2019.
"And these companies are offering us nothing, saying their hands have been tied by the government. That means, in real terms, with inflation running ahead at nine per cent, 10 per cent, and even 11 per cent this year, according to which index you use, that they are being told to take a real terms pay cut. And that is not acceptable.
"Strike action is, now, the only option available but we are always open to talks if the train companies, or the government, want to talk to us and make a fair and sensible offer."