Ser harina de otro costal

/seɾ a·ˈɾi·na ðe ˈo·tɾo kos·ˈtal/

To be flour from another sack.

Frequency

ConversationCommon

JournalismCommon

LiteraryOccasional

AcademicRare

In English

that's a different matter; **that's a different matter**; **that's another story**; **that's a separate issue**; **that's a different kettle of fish**

Meaning

Ser harina de otro costal means to be a different issue altogether, unrelated to the matter under discussion.

Examples

Eso ya es harina de otro costal.

That's a different matter.

Lo que ocurrió después es harina de otro costal.

What happened afterwards is another story.

Una cosa es discutir y otra faltar al respeto. Eso es harina de otro costal.

Arguing is one thing; being disrespectful is a completely separate issue.

The expression is used to separate one topic from another, especially when someone tries to introduce an argument that is not directly relevant.

A discussion about prices may suddenly turn to politics.

Someone might reply:

Eso es harina de otro costal.

The idiom indicates that the new subject deserves separate consideration.

Used when

changing to a different topic
rejecting an irrelevant comparison
distinguishing between two separate issues
clarifying that one matter should not be mixed with another
acknowledging that a different problem exists

Origin

The expression comes from traditional milling and trade.

Flour stored in one sack was expected to come from the same grain and to have the same quality.

Flour from another sack represented a different product that should not be mixed with the first.

Spanish extended this practical image into a metaphor for ideas, arguments and situations that belong to different categories.

Cultural note

Spanish speakers often use this idiom to keep a conversation focused.

Rather than saying simply that someone has changed the subject, they indicate that the new topic belongs in a completely different discussion.

The expression is especially common in debates, interviews and family conversations.

Did you know?

Although almost nobody thinks about sacks of flour anymore, the expression has survived for centuries with remarkable vitality.

It remains one of the most elegant and natural ways in Spanish to separate two ideas without rejecting either of them.

When a Spaniard says "Eso es harina de otro costal," everyone immediately understands that the conversation has entered completely different territory.

For English speakers

Do not translate the expression literally.

English speakers would never say:

That's flour from another sack.

Instead, use expressions such as:

That's a different matter.
That's another story.
That's a separate issue.
That's a different kettle of fish.

Choose the expression that best matches the formality of the conversation.