Currently, we have four data plans:
Grandfathered AT&T Unlimited Plus HotSpot Plan – We've had this plan since November of 2017 when our MIA Membership paid off in a big way by warning us that this plan would be going away. And, if we wanted a good unlimited AT&T plan to grab a hotspot before it goes away. We did, and we still have this true unlimited plan today even though it went away in late 2017.
Verizon Unlimited Plan via Mobile Must Have – This plan is via their data broker and is also no longer available, unfortunately. We pay $120/mo for this plan.
AT&T Unlimited (5000GB fair use cap) via Mobile Must Have – This plan is still available for $349 then $160/mo at the time of writing this FAQ (2021-02-24). It's a steep price, but unlimited data plans are hard to find these days. We locked in at $120/mo.
Sprint Unlimited Plan via Calyx Institute – The Calyx Institute offers this plan as part of a membership for $500/yr ($400 for subsequent years). With the 3 plans above, this one is just to have just in case we're in an area saturated by AT&T and Verizon users (a big rally or something), or if it happens to be the only thing around. We've fired it up in our Pepwave a few times to test it. It works but was very slow where we tried it.
With the above plans, we primarily have the first 2 active most of the time (our router can have 2 modems active at once and bonded together). Yes, we pay a LOT for a versatile and resilient data solution, but our job depends on it.