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AT&T vs. Boost Mobile: iPhone 18 Pro Max for 4 lines
For 4 lines of iPhone 18 Pro Max over 36 months, Boost Mobile's Unlimited+ beats AT&T's Extra 2.0 by $1,128. The monthly plan price is the single biggest driver of that gap. Both sides are backed by confirmed plan pricing.
AT&T (24 months) and Boost Mobile (24 months) spread its device credit over fewer than 36 months, so the bill drops partway through.
AT&T
Extra 2.0 · Buy unlocked (Apple financing)
$81.25/mo per person, 4 lines
$11,699 over 36 months · $324.99/mo household
$397.60/mo for 24 months, then $181.08/mo once the device is paid off.
How we calculate thisBoost Mobile
Unlimited+ · Buy unlocked (Apple financing)
vs. AT&T unlocked (Apple financing) over 36 months
$73.42/mo per person, 4 lines
$9,361–$10,572 over 36 months · $260.02–$293.66/mo household
$365.72/mo for 24 months, then $149.20/mo once the device is paid off.
- Activation fee unconfirmed,
- Provider fees unconfirmed
Resolves once Boost Mobile's activation fee is confirmed and Boost Mobile's provider fees are confirmed.
$0–$1,051 more than your current bill over 36 months — for 4 lines on Unlimited+
Plus 4 new phones and setup: $5,041–$5,201, net of trade-in/resale credit.
Plan $30.00/mo + device $54.13/mo + $40.00 upfront − $38.97 cashback
iPhone 18 Pro Max paid over 24 months at 0% APR via Apple Card Monthly Installments, with 3% cashback credited once.
Sales tax on the device (varies by state, typically charged upfront on full MSRP) is not included in the totals above.
Boost Mobile's per-line activation fee isn't confirmed — shown here as $40.00 (worst case, based on the highest verified activation fee in this dataset); best case assumes $0.
We don't have a resale value for a iPhone 16 in this condition yet, so it counts as $0 here.
Plan $30.00/mo + device $54.13/mo + $40.00 upfront − $38.97 cashback
iPhone 18 Pro Max paid over 24 months at 0% APR via Apple Card Monthly Installments, with 3% cashback credited once.
Sales tax on the device (varies by state, typically charged upfront on full MSRP) is not included in the totals above.
Boost Mobile's per-line activation fee isn't confirmed — shown here as $40.00 (worst case, based on the highest verified activation fee in this dataset); best case assumes $0.
We don't have a resale value for a iPhone 16 in this condition yet, so it counts as $0 here.
Plan $30.00/mo + device $54.13/mo + $40.00 upfront − $38.97 cashback
iPhone 18 Pro Max paid over 24 months at 0% APR via Apple Card Monthly Installments, with 3% cashback credited once.
Sales tax on the device (varies by state, typically charged upfront on full MSRP) is not included in the totals above.
Boost Mobile's per-line activation fee isn't confirmed — shown here as $40.00 (worst case, based on the highest verified activation fee in this dataset); best case assumes $0.
We don't have a resale value for a iPhone 16 in this condition yet, so it counts as $0 here.
Plan $30.00/mo + device $54.13/mo + $40.00 upfront − $38.97 cashback
iPhone 18 Pro Max paid over 24 months at 0% APR via Apple Card Monthly Installments, with 3% cashback credited once.
Sales tax on the device (varies by state, typically charged upfront on full MSRP) is not included in the totals above.
Boost Mobile's per-line activation fee isn't confirmed — shown here as $40.00 (worst case, based on the highest verified activation fee in this dataset); best case assumes $0.
We don't have a resale value for a iPhone 16 in this condition yet, so it counts as $0 here.
Data verified September 10, 2026.
AT&T's provider fee: $5.27/line (PA label; varies by state). Boost Mobile's provider fee: provider fee not yet confirmed.
Frequently asked
Which is cheaper for 4 lines of iPhone 18 Pro Max: AT&T or Boost Mobile?
Boost Mobile's Unlimited+ costs $10,572 over 36 months for 4 lines of iPhone 18 Pro Max, $1,128 less than AT&T's Extra 2.0 at $11,699.
What's the effective monthly cost of iPhone 18 Pro Max on AT&T vs. Boost Mobile?
AT&T works out to $324.99/mo and Boost Mobile to $293.66/mo, each the 36-month total divided evenly by 36 — not necessarily the bill you'd see in any single month.
Are these AT&T and Boost Mobile prices confirmed?
AT&T's total is not yet independently verified, and Boost Mobile's is a computed worst/best estimate, pending a promo or fee confirmation. See the confidence badge on each card, and our methodology page, for what that means.