There are three elements you should focus on while trying to find the best pay as you go SIM card.
• The first is the relevance of the SIM. You may have an old phone, a 3G compatible phone or one that is compatible with 4G LTE. You will need to pick the SIM card accordingly. You can get a 3G SIM that is backwards compatible. You can get a 4G LTE SIM that works on 3G and will move to 2G data depending on the network reception. But you cannot use a 4G LTE SIM in a phone that is not compatible.

• The second element is the size of the SIM. The more advanced the phone, the smaller your SIM should be. You may need a standard SIM, micro SIM or nano SIM depending on the phone you have.

• The third element is the network. Do not look for the best pay as you go SIM card based on the cost of the SIM or if it is free, unless you are sure of the network. You also need to check the charges.

To give you a fair idea of what the prevailing costs are of some of the best pay as you go SIM card, H2O Wireless will charge you $9.95 for a data only SIM, so would AT&T for an internet only SIM. Simple Mobile is offering a free pay as you go SIM right now. The standard SIM from Simple Mobile usually costs $9.95. You must check if the offer is still applicable. AT&T has unlimited plans in its SIM cards starting at $19.95. T-Mobile will charge you $4.95 but get you access to unlimited features in the plans. NET10 charges $9.95. Ultra Mobile charges $9.95.
These are some of the deals available right now. They are subject to change. It is also possible that the prices will remain the same. Not all telecom networks or service providers will have pay as you go plans so before you get a SIM, check if you are signing up for a plan or pay as you go deals. Prepaid plans are not pay as you go since you will commit to a bare minimum monthly payment. You will get some validity and keep paying the committed amount regardless of your usage. Look for the cheapest per minute charges, text charges and data usage charges. Pay as you go deals and prepaid plans are similar in some ways and dissimilar in some ways.