Should I Keep My Grandfathered Plan?

1. What do you actually pay, all-in?

Not the plan rate — the bill. Pull the most recent one and total everything attached to your line: the base rate, the per-line access charge, the administrative charge, regulatory recovery, and any surviving device or feature fee. Grandfathered plans are unusually prone to fee creep, because carriers can't raise a protected base rate but can and do raise everything around it.

The comparison number that matters is your all-in per-line cost. Hold it against these, which are current and include taxes and fees where noted: Total MAX 5G BYO at $25/mo all-in on Verizon's network with unlimited hotspot; Visible+ at $35/mo all-in on Verizon; US Mobile Unlimited Premium at $32.50/mo; Cricket Supreme at $60/mo on AT&T with priority data; T-Mobile Experience More at $85/mo with taxes included.

2. How much data do you really use?

This is where most grandfathered decisions go wrong. People protect an unlimited plan while using 12GB a month. Check the real number in your carrier's app — it's per line and it covers the current billing cycle — and look at three or four months rather than one.

• Under 20GB — you're paying a premium for headroom you never touch. Almost any current plan wins.
• 20 to 50GB — still comfortably inside the premium-data allowance on current unlimited plans; most cap between 35GB and 100GB before deprioritization.
• Over 50GB consistently — now the grandfathered plan starts to earn its keep, and the comparison gets closer. Check whether your old plan is actually unthrottled at that level, because many aren't.
• Heavy tethering — hotspot is metered separately on nearly every current plan, and it's the one place a genuinely unlimited legacy plan can still be worth real money.

3. Is your old plan still unthrottled?

Several legacy unlimited plans had throttling or deprioritization added after the fact — you kept the word unlimited and lost the behaviour. If your speeds collapse after a certain point each month, you're already on a capped plan that's priced like an uncapped one, and the main reason to stay has quietly evaporated.

4. Has your rate been rising?

A grandfathered rate is only worth protecting if it's actually protected. Compare this month's bill to one from two years ago. If it has drifted upward through fee increases, you don't have a locked rate — you have an unlisted plan that gets repriced without the marketing that accompanies a public change. That's a weaker position than a current plan with published terms, and materially weaker than an MVNO whose advertised price is the whole price.

5. Would you genuinely lose something?

Sometimes yes. Be honest about which of these apply to you, because they're the real reasons to stay:

• Truly unlimited, unthrottled tethering — rare, and worth keeping if you have it.
• Multi-line pricing that no longer exists at the same total, which happens on old family plans with several lines.
• A bundled discount tied to employment, an association, or a home-internet package that doesn't survive a plan change.
• Coverage in a specific place where you've tested the alternatives and they genuinely don't work.

What you almost certainly won't lose: your number, your phone, or the ability to come back. Porting out is reversible in practice, though not to the grandfathered rate — which is the one asymmetry worth respecting. Once you leave, that plan is gone for good.

The decision

• Keep it if: you use over 50GB with genuinely unthrottled data, you tether heavily on an unlimited allowance, or a multi-line or bundled discount makes the total unbeatable.
• Leave it if: you're under 30GB, paying over $45 all-in for one line, or your rate has been creeping up through fees.
• Test before you leave either way. Free eSIM trials let you check the alternative on your own phone without touching your existing line.