In most cases yes your security system will work without a landline telephone attached. In addition to removing the phone line from the actual alarm panel you will need to purchase either an compatible internet, cellular, dual-path or Tri-Path alarm communicator. One option you will have in learning whether your security system will work without a landline is to search our knowledge base for your security system make and model followed by alarm monitoring ie 2GIG
Advantages to Cutting your Landline:
1) By cutting your phone line you have one less bill to pay & save money. Internet or Cellular monitoring options typically are not much more expensive per month. Phone line/Internet monitoring starts at $10/month and Cellular Monitoring starts at $15/month no long-term contract. Not a big difference in cost.
2) By cutting your phone line and moving to cellular alarm monitoring services you are actually upgrading your security system's reliability. Phone lines and Internet lines are usually vulnerable because they are posted on the outside perimeter of your home or business. This means that if an intruder was to cut your meter box, phone line, internet lines your alarm system would not be able to transmit its signals to the central station receiver. Where cellular alarm communicators are powered off of your alarm systems backup battery and even if your lines are cut our central station will receive your alarm signals and activate dispatching protocols.
3) Not in all cases but if you choose to cut your phone lines there are internet or cellular communicators that can provide you with remote arming/disarming abilities, text/email notifications, remote control of z-wave automation devices and or the ability to view selected IP cameras all from your smart devices.