If phone has no dial tone, before calling your service provider. Try these simple trouble shooting steps.
1.Check phone cord if properly connected to cradle or base where the phone handset resides.
2.Make sure the other end of the cord is connected to phone jack.
3.For corded phone handset. Make sure spiral cord, and cord from the jack are clip in properly.
4.For cordless type of handset. Check If the base of the phone is connected to power source.
5.Check battery or change battery of cordless handset if needed.
6.Unplug phone from jack, plug in after two minutes. If you have fax machine, unplug as well.
7.If you have cordless phone unplug also from power source.
8.If you have more than one handsets unplug them all from the jack. After two minutes, plug in one by one. Check for dial tone as you plug one after the other. This is to isolate the possibility of one handset causing the no dial tone issue. Unplug that handset causing the no dial tone permanently. If you have one handset and you have several jacks. Try plugging in the handset to the other jacks to isolate a jack trouble.
9.If phone and internet modem are using same jack separated only by splitter. Try to use a new splitter.
10.Call your home phone. If you hear a not in service recording. Check if bills have been paid. If busy signal, check if handset rests properly on the cradle.
After doing these trouble shooting, and still will not fix the no dial tone issue. Call your service provider.