Strike action is set to bring railways in Hertfordshire to a halt this week.

Train crew, station staff and teams responsible for running the track and signalling are part of a walkout impacting 13 train companies and Network Rail.

RMT member staff at Greater Anglia, LNER and London Northwestern Railway - among others - are taking part in industrial action in Hertfordshire.

Great Northern and Thameslink staff are not striking, but many routes on the network will be unable to run due to a lack of signalling teams.

The Centre for Economics and Business Research think thank estimated that the strikes - which take place on June 21, 23 and 25 - could carry a £91 million price tag for the UK economy. London alone is set to lose £52m as some commuter routes close entirely.

But passengers who have bought a ticket for train travel during strike week may not need to forfeit their money if they choose not to travel.

Rail firms are offering refunds to affected passengers:

Avanti West Coast

Strike information page: https://www.avantiwestcoast.co.uk/travel-information/plan-your-journey/strike

Staff at Avanti are striking, with limited trains between London Euston, Watford Junction, North Wales, the North West and Scotland.

An Avanti spokesperson said: "Customers with tickets dated June 21, 23 or 25 can use these tickets to travel on any non-strike date between now and Tuesday, June 28.

"Customers with existing tickets for travel from Tuesday, June 21 to Sunday, June 26 who no longer wish to travel can claim a full refund with no admin fees from their point of purchase."

This means passengers who purchased a ticket from Avanti's own website and cannot travel may fill in an online form. Station staff can assist passengers with tickets bought in-person.

Season ticket holders may continue to travel, and can claim "delay repay" within 28 days if their train is delayed by 15 minutes or more. Passengers with season tickets lasting one month or more may claim up to 100 percent delay repay for strike day disruption.

Chiltern Railways

Strike information page: https://www.chilternrailways.co.uk/strike

A Chiltern Railways spokesperson said there will be no trains through Rickmansworth and Chorleywood in Hertfordshire on strike days.

A spokesperson said: "Customers who have already purchased tickets can claim a full fee free refund from the original ticket retailer or can amend their ticket."

Passengers can apply for compensation if their train is delayed by 15 minutes or more against the advertised time.

Season ticket holders may use the "delay repay" scheme for compensation if they cannot travel due to strikes. Flexi season ticket holders must wait until their ticket has expired and any unused travel days can be refunded, the spokesperson said.

Greater Anglia

Strike information page: https://www.greateranglia.co.uk/travel-information/rail-strike-travel-advice

Greater Anglia's strike timetable includes trains on main routes only, with no trains on branch or rural train lines in Hertfordshire, Essex, Cambridgeshire, Suffolk and Norfolk.

"You can already get a full refund on unused daily tickets," a spokesperson said.

"This is for when you decide not to travel after booking because your intended service is cancelled, delayed or rescheduled."

To receive a refund, ticket holders should return to their point of purchase. Anybody who bought their ticket with Greater Anglia online can request a refund by logging into their account, emailing sales.support.greateranglia@trainsfares.co.uk, or speaking to the firm's Web Support Team on 0345 600 7245 (option 6).

Season ticket holders with monthly (or longer) passes can claim strike day "delay repay" online by selecting the "Did Not Travel" option.

Hull Trains

Strike information page: https://www.hulltrains.co.uk/travel-information/industrial-action

A Hull Trains spokesperson said that although its staff are not striking, the firm can only run trains between 7.30am and 6.30pm on strike days, between London King's Cross and Doncaster only.

"Customers with existing tickets for travel on June 21, 23 or 25 can get in touch to change their travel date seven days either side of your original booked date," a spokesperson said.

"Alternatively, customers can claim a full refund if they do not wish to travel."

Hull Trains' "Get In Touch" webpage is online: https://www.hulltrains.co.uk/support-and-contact/contact-us

Lumo

Strike information page: https://www.lumo.co.uk/plan-your-journey/industrial-action

Lumo staff are not striking, but some trains between London King's Cross, Stevenage and Edinburgh may be affected.

"If a service has been cancelled, customers are able to claim a fee-free refund through the normal channels," a Lumo spokesperson said.

"If you purchased your ticket via Lumo, you can apply for a refund on your unused ticket via our portal. If you purchased your ticket from another retailer, such as the Trainline, please request your refund directly from your point of purchase."

The Lumo portal is online: https://refunds.lumo.co.uk/

LNER

Strike information page: https://www.lner.co.uk/travel-information/Industrial-action/

LNER routes may be disrupted, with the final London King's Cross to Edinburgh departure set to depart at 2pm.

"If your train was cancelled you will be entitled to a full refund back to your original payment card," an LNER spokesperson said.

This can be done on the LNER Your Account section of the website (https://www.lner.co.uk/).

They added: "If your train is still running but you no longer want to travel, you can get an e-voucher refund that can be used on our website or LNER app to book any train in Great Britain."

Season ticket holders with passes lasting one month or more can request a 100 percent refund if they choose not to travel on strike days, with up to six journeys' compensation on offer across the three strike days.

London Northwestern Railway

Strike information page: https://www.londonnorthwesternrailway.co.uk/travel-information/journey-planning/service-disruptions/industrial-action

London Northwestern Railway will run a reduced service between London Euston, Watford Junction and the Midlands throughout the strike period. There will be no trains between Watford Junction and St Albans Abbey.

A spokesperson said: "If you have purchased a ticket and your train is cancelled or delayed, and you choose not to travel, you can return the unused ticket to your point of purchase for a full refund.

"Alternatively, if you have booked an Advance ticket to travel on our services, you will be able to use your ticket the day before or after at no additional cost.

"If you hold a season ticket, you will be entitled to delay repay compensation if you travel on an affected date."

Great Northern, Southern or Thameslink

Strike information page: https://www.thameslinkrailway.com/travel-information/plan-your-journey/industrial-action

Govia Thameslink Railway staff voted to take "action short of a strike" rather than opt for a full-scale walkout. Great Northern, Southern and Thameslink trains may still be impacted by the Network Rail industrial action.

A spokesperson said: "While we cannot fund taxi or hotel bills, if you decide to travel during a strike period and your chosen train is affected, you may be able to use your ticket on an alternative Southern, Thameslink or Great Northern route.

"Where disruption prevents you from completing your journey for which your ticket is valid and is being used, we will - where we reasonably can - provide you with alternative means of travel to your destination, or if necessary, provide overnight accommodation for you.

"If you choose not to travel because your service has been cancelled, delayed or rescheduled you will be entitled to a refund."

They added that season ticket holders who follow the "do not travel" advice can make a delay repay claim for 120+ minutes on each strike day (https://www.thameslinkrailway.com/help-and-support/journey-problems/delay-repay).

The Trainline

Strike information page: https://www.thetrainline.com/trains/great-britain/industrial-action

A The Trainline spokesperson said: "If you think the rail strikes might affect your upcoming journey, we’re here to support you and will contact you with details of any changes to the train you’ve booked.

"If you’ve booked with us and your train has been cancelled or rescheduled, you will be entitled to a fee-free refund if you choose not to travel, or you can rearrange your trip without a fee."