THREE Mobile customers will want to know how to check the network in their area if they suspect that there's been an outage.
The mobile network last went down for hundreds of customers on December 1.
Customers said that they had no signal, couldn't make calls or had no access to the internet.
We explain how to find out if there are problems with Three, including issues with calls, texts and internet.
Is Three Mobile down?
Three Mobile, which has 10million customers in the UK, last saw problems with its service on December 1.
Around 700 customers complained online that they had no signal and couldn't access the internet.
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Three Mobile last went down in May.
Customers said that they couldn't make or take calls or access the internet on social media.
How do I check the service status of Three Mobile?
Three Mobile has a dedicated web page where you can find out if there are any problems in your area.
Three Mobile offers customers a service update page on their website.
To then find out if there are any problems, simply enter your postcode.
This aims to keep customers in the know and should confirm when any issues are resolved.
How can I contact Three Mobile and am I entitled to compensation?
If you're suffering issues with your internet, call or mobile services then you may be entitled to compensation.
Internet firms usually pay out £8 for each say that broadband and phone service is not repaired after two full days of no service.
If you're a mobile customer and you suffer from a lack of service then depending on the circumstance you may be entitled to a refund or account credit.
If you're without service for a sustained period of time then you may have the right to leave without incurring a fee.
If you still want to complain to Three Mobile about an issue, you can contact the firm via phone, online or pop by a branch.
You can also speak to Three Mobile via its live chat service on the app.
If your problem is still unresolved after eight weeks, you can complain to an independent Alternative Dispute Resolution (ADR) scheme.
We've also rounded up everything you need to know about checking the status of Virgin Media.
If you're a Sky customer, here's what you need to know about checking its service status.
TalkTalk households can use this guide to see how to get in contact with the telecoms company.
You can also join our new Sun Money Facebook group to share stories and tips and engage with the consumer team and other group members.