Is zakaat al-fitr due from one who did not fast in Ramadaan because of a valid excuse?
Question

                Is zakaat al-fitr due from one who did not fast all Ramadaan because he was travelling or was sick?.
Praise be to Allah.
    The majority of scholars, including the four imams and 
    others, are of the view that zakaat al-fitr is due from the Muslim even if 
    he did not fast Ramadaan. No one else differed from that except Sa’eed ibn 
    al-Musayyab and al-Hasan al-Basri, who said that zakaat al-fitr is due only 
    from those who fasted. But the correct view is that of the majority, because 
    of the following evidence: 

    1 –The general meaning of the hadeeth which is the basis for 
    zakaat al-fitr being obligatory:  

    It was narrated that Ibn ‘Umar (may Allaah be pleased with 
    him) said: The Messenger of Allaah  (peace and blessings of Allaah be 
    upon him) enjoined zakaat al-fitr, a saa’ of dates or a saa’ of barley, upon 
    everyone, slave or free, male or female, young or old, and he enjoined that 
    it be paid before the people went out to pray. Narrated by al-Bukhaari 
    (1503) and Muslim (984). 

    The word “young” includes small children who cannot fast. 

    2 – When charity and zakaah are enjoined, it is usually to 
    help the poor and needy, and is aimed at achieving some degree of social 
    security, and the most obvious case is zakaat al-fitr, which is enjoined 
    upon young and old, free and slave, male and female, and the Lawgiver did 
    not stipulate any minimum threshold (nisaab) or the passage of one year for 
    it to be obligatory. Hence the fact that it is obligatory for those who did 
    not fast in Ramadaan, with or without an excuse, is implied in the purpose 
    for which this zakaah is prescribed. 

    3 – With regard to the argument of those who quoted as 
    evidence the words of Ibn ‘Abbaas (may Allaah be pleased with him): The 
    Messenger of Allaah  (peace and blessings of Allaah be upon him) 
    enjoined zakaat al-fitr as a purification for the fasting person from idle 
    talk and obscene speech, and to feed the poor. Narrated by Abu Dawood (1609) 
     

    They said: The words “as a purification for the fasting 
    person” means that zakaat al-fitr is obligatory only for those who fasted. 
    Al-Haafiz Ibn Hajar responded to that in al-Fath (3/369) where he 
    said: 

    My response is that mentioning purification refers to the 
    usual case (as most people fast), just as it is also required of those who 
    did not commit sin, such as one who is very righteous or one who became 
    Muslim a moment before the sun set. End quote.   

    What this means is that in most cases zakaat al-fitr is 
    prescribed because it is a purification for the one who fasted, but 
    attaining this purification is not a condition of it being obligatory. A 
    similar case is the zakaah of one’s wealth, which has also been prescribed 
    in order to purify the soul:  

    “Take Sadaqah (alms) from their wealth in order to purify 
    them and sanctify them with it, and invoke Allaah for them. Verily, your 
    invocations are a source of security for them; and Allaah is All-Hearer, 
    All-Knower”

    [al-Tawbah 9:103]

    Despite that zakaah is obligatory in the case of wealth 
    belonging to a small child who does not need to be purified, because no bad 
    deeds are recorded for him. 

    Shaykh Ibn Jibreen gave another response, and said: 

    It is paid on behalf of children and those who are not 
    accountable, and those who did not fast because of an excuse such as 
    sickness or travel. So the purification is for the guardians of those who 
    are not accountable, and it is a purification for the one who did not fast 
    because of an excuse, on the assumption that he will fast once the excuse is 
    no longer in effect, so it is purification in advance, before he fasts or 
    completes his fast. End quote. 

    Fataawa al-Zakaah (zakaat al-fitr/2)

    And Allaah knows best.