If a jamaah haji misses the stoning on one of the days of Tashriq (11th, 12th, or 13th of Dhul-Hijjah), the majority of scholars hold that they may make it up the following day. The jamaah haji should stone for the missed day first, then stone for the current day. Sheikh Ibn Baz explained that the days of stoning are interconnected — the stoning of one day can be deferred to the next, though this is not the Sunnah and should only be done when there is a valid excuse.
If a jamaah haji misses the stoning entirely — all days of Tashriq pass without stoning any Jamarah — the time for stoning has expired and cannot be made up. In this case, the jamaah haji must offer a dam (sacrifice of a sheep) as penalty for omitting the wajib act of stoning. Sheikh Ibn Uthaymeen clarified that the stoning is classified as wajib (wajib), not a rukun (pillar) of Haji, meaning that omitting it does not invalidate the Haji itself but requires a penalty.
The Permanent Committee noted that missing the stoning due to genuine inability — such as severe illness or being physically unable to reach the Jamarat even with assistance — requires appointing a proxy to stone on the jamaah haji's behalf. If no proxy was appointed and the time passed, a dam suffices. Al-Fawzan added that if the jamaah haji missed the 11th day but stoned on the 12th and 13th, they should stone for the missed day (21 pebbles total for the 12th — 7+7+7 for the missed day, plus 21 for the current day) if they remember.