It is a question to raise, not a result to assume. Alternate chargeability through an accompanying spouse is reviewed on the facts of your case; it is not granted automatically because it would be favourable. A joining legally married spouse adds US$15,000 and a further US$1,000,000 qualifying gift.
Raise it before you commit to a schedule
Suppose the spouses were born in countries with different waiting times. Review the conditions for spousal cross-chargeability and the required evidence during initial planning. Official instructions recommend including family at the outset for the stated program benefits, but inclusion does not guarantee favorable chargeability. Later inclusion needs its own review and should not be assumed free.
Eligible joining children generally must be unmarried and under 21; assess any applicable CSPA protection using the individual case facts. Map the applicant, spouse and every unmarried child under 21 separately, showing relationship, intended inclusion, payment responsibility and immigration eligibility. If a child’s age or marital status may change during processing, raise that issue explicitly. A child who does not apply is simply not covered, and being over 21 or married removes eligibility as a derivative in any case.