When is it forbidden for a traveller to break the fast?

The Qur’aan and Sunnah, and the consensus of the ummah,
indicate that a person who is travelling during the day in Ramadaan is
allowed not to fast. Allaah says (interpretation of the meaning): 

“and whoever is ill or on a journey, the same number [of
days which one did not observe Sawm (fasts) must be made up] from other
days”

[al-Baqarah 2:185] 

See question no. 37717. 

The fuqaha’ (may Allaah have mercy on them) stated that the
traveller who is allowed not to fast is one who is travelling the distance
at which it becomes permissible to shorten the prayers, and is travelling
for a permissible purpose. 

If a person is travelling a distance shorter than that at
which it becomes permissible to shorten the prayers or he is travelling for
sinful purposes, then it is not permissible to shorten the prayers. The same
applies to one who travels in order to be able to break the fast: it is
haraam for him to travel and to break the fast. 

According to the majority of scholars, the distance at which
it becomes permissible to shorten the prayers is four stages, which is
equivalent to approximately 80 kilometers. Some scholars are of the view
that it cannot be reckoned by distance, but is rather what the people
describe as travelling. 

See question no. 38079. 

The view that the one who is traveling for sinful purposes is
not allowed to break his fast or avail himself of any of the other
concessions granted to travellers, such as shortening the prayers, is the
view of the Maalikis, Shaafa’is and Hanbalis. 

See al-Mughni, 2/52 

They gave the reason for that as being that being allowed to
break the fast (whilst travelling) is a concession, and the one who is
travelling for sinful purposes does not deserve any concession. Some of them
quoted as evidence the verse in which Allaah says (interpretation of the
meaning): 

“But if one is forced by necessity without willful
disobedience nor transgressing due limits, then there is no sin on him”

[al-Baqarah 2:173] 

The point here is that Allaah has not permitted the eating of
dead meat to those who are willfully disobedient or who transgress the
limits, because they are sinners. They said: The one who is willfully
disobedient is the one who rebels against the ruler, and the one who
transgresses the limits is the one who rebels against society and commits
highway robbery (like a bandit). 

The Hanafis are of the view that the one who travels for
sinful purposes is allowed to break the fast, shorten the prayers and so on.
This is also the view favoured by Ibn Taymiyah (may Allaah have mercy on
him).  

See al-Bahr al-Raa’iq, 2/149; Majmoo’ al-Fataawa,
24/110 

They did not agree with the majority’s use of this verse as
evidence. They said: The one who is willfully disobedient is the one who
seeks haraam food despite the fact that he is able to obtain halaal food,
and the one who transgresses the limits is the one who takes more than he
needs. 

With regard to the one who travels in order to break the
fast, he is trying to find ways around the rulings of sharee’ah, so he
should be punished by being denied the concession. 

It says in Kashshaaf al-Qinaa’, 2/312, which is a
Hanbali book: 

But if he travels in order to break the fast, they both
become haraam for him, i.e., travelling and breaking the fast, because there
is no reason for his travelling except breaking the fast. It is haraam for
him to break the fast because he has no legitimate reason to allow him to do
that, and it is haraam for him to travel because it is a means to break the
fast in a haraam manner. End quote. 

The traveller does not have the right to break his fast
except after he has left behind the built-up area of his city or village. It
is haraam to break his fast before that, because he is still a non-traveller
in that case. See question no. 48975. 

Based on this, it is haraam for a traveller to break his fast
in several cases, including the following: 

1-    
When he is travelling but the
distance does not reach the distance at which it becomes permissible to
shorten the prayers.

2-    
When his journey is not
permissible according to the majority of scholars.

3-    
When he is travelling in order
to break the fast.

4-    
When he is travelling and wants
to break the fast before leaving the houses of his village or city.

5-    
There is a fifth case in which
it is haraam for a traveller to break the fast according to the majority of
scholars. That is when he is staying in the place to which he has traveled
for more than four days. Other scholars say that the concessions of travel
apply to the traveller no matter how long he stays. See question no.
21091. 

And Allaah knows best.