Is fish considered meat in the 9s?

The prohibition of eating meat during the Nine Days (the first nine days of Av) does not apply to fish. Fish is permitted throughout the Nine Days, including during the week of Tisha B'Av itself, and is not considered "meat" (basar) for the purposes of this mourning custom.

Key Takeaways

Fish is permitted during the Nine Days and is not included in the custom to abstain from meat.
The restriction applies to beef, poultry, and lamb — not fish.
Some authorities permit poultry in certain circumstances, but fish has no such debate.
Fish is also not subject to the meat-and-wine restriction that applies during this period.
On Shabbat, all meat and wine are permitted, as Shabbat overrides the mourning practices of the Nine Days.

Detailed Answer

The Custom to Abstain from Meat

The Shulchan Arukh (Orach Chayim 551:9) records the Ashkenazic custom (minhag) to refrain from eating meat and drinking wine during the Nine Days — from Rosh Chodesh Av through Tisha B'Av:

"There are those who are accustomed not to eat meat and not to drink wine during this week [of Tisha B'Av]... and there are those who add from Rosh Chodesh..."

[Shulchan Arukh, Orach Chayim 551:9]

The Rama (Rabbi Moshe Isserles) notes that the Ashkenazic custom extends this restriction from Rosh Chodesh Av onward. Sephardic communities generally restrict meat only during the week in which Tisha B'Av falls.

Why Fish Is Not Included

The restriction on meat is rooted in the concept of simcha (joy) — meat and wine are associated with festivity and celebration. The Talmud states:

"אֵין שִׂמְחָה אֶלָּא בְּבָשָׂר וְיַיִן" — "There is no joy except with meat and wine."

[Pesachim 109a]

Fish, by contrast, is not included in this Talmudic association of meat with simcha. It is considered a more ordinary food and therefore carries no symbolic association with the joy we are withholding during this period of mourning for the destruction of the Temple (Beit HaMikdash).

What "Meat" Means in This Context

The restrictions apply to:

Beef and lamb (certainly)
Poultry — included by most Ashkenazic authorities; the Shulchan Arukh (551:10) notes a view that poultry is forbidden as well
Meat-based broths and gravies — many authorities restrict these too

Fish is explicitly excluded by virtually all poskim (halachic decisors), including Rav Moshe Feinstein and the Mishnah Berurah, who confirm that fish is fully permitted throughout the Nine Days.

[Mishnah Berurah 551:63]

Shabbat Exception

As the Shulchan Arukh records, on Shabbat during the Nine Days, meat and wine are fully permitted — in fact, one should honor Shabbat with meat if possible. Fish, of course, is also permitted on Shabbat.

Broader Context: Kashrut vs. Mourning Customs

It is worth noting that this is a mourning custom (minhag avel), not a kashrut prohibition. Fish is kosher year-round [Leviticus 11:9-12 — fish with fins and scales are permitted]. The Nine Days restriction is an additional layer of practice expressing grief over the Temple's destruction, and fish simply was never part of that custom.

For personal guidance on your specific community's customs, consult your local rabbi or posek.