Buenas tardes, familia.

Because tardes is a feminine plural noun, so the adjective has to agree with it.

• tarde = feminine noun
• tardes = plural
• so the greeting becomes buenas tardes

Spanish greetings like this often follow normal gender and number agreement:

• buenos días
• buenas tardes
• buenas noches

This is just how the fixed greeting works in Spanish. Even though English says good afternoon in the singular, Spanish uses the plural expression buenas tardes.

It is best to learn it as a set phrase, just like:

• buenos días
• buenas tardes
• buenas noches

You do not normally change it to singular in this context.

Because familia means family as a single unit or group. Even if you are talking to several people, Spanish can address them collectively as familia.

So Buenas tardes, familia is like saying:

• Good afternoon, family
• or more naturally, Good afternoon, everyone / family

It is common to use a singular collective noun this way.

Yes, the comma is natural here because familia is being used in direct address.

The speaker first says the greeting:

• Buenas tardes

Then directly addresses the listeners:

• familia

So the comma helps show that familia is who you are speaking to, not part of the greeting itself.

Yes, but they are not exactly the same.

• Hola, familia = a simpler, more casual greeting
• Buenas tardes, familia = a time-based greeting, a little more formal or structured
• Buenas tardes a la familia = understandable, but less natural if you are directly addressing them

When speaking directly to the group, Buenas tardes, familia is the most natural option.

In general, it is used from around noon or early afternoon until evening, before buenas noches starts.

The exact time can vary by country or situation, but a rough guide is:

• buenos días = morning
• buenas tardes = afternoon / early evening
• buenas noches = night

In many places, buenas tardes can still be used until it is clearly nighttime.

Yes. In many Spanish-speaking places, buenas tardes can work both as:

• a greeting when arriving
• and a polite expression when leaving during that time of day

Context tells you whether it means hello or something closer to have a good afternoon.

No. This sentence is just a greeting, so no subject pronoun is needed.

Spanish often leaves out subject pronouns, and in greetings they usually do not appear at all.
Buenas tardes, familia is complete by itself.

It is generally neutral to polite.

• Buenas tardes is a polite standard greeting
• familia makes it warmer and more personal

So together it sounds friendly, respectful, and natural. It could be used in a home, a community gathering, a church setting, a video message, or even a presentation to a familiar audience.

Normally, no.

You would usually write:

• Buenas tardes, familia.

Spanish capitalizes words much like English does in normal sentences: only proper nouns and sentence beginnings get capitals.
So familia stays lowercase unless it is part of a title or stylistic choice.

In some places, yes. Buenas is a shortened informal greeting that comes from expressions like buenos días, buenas tardes, or buenas noches.

However:

• Buenas tardes is more complete and standard
• Buenas is more casual and depends on region and context

For a learner, Buenas tardes, familia is the safer and clearer form.

No. It can also be used more broadly for a close-knit group.

Depending on context, familia might refer to:

• your real family
• a church community
• a work team with a warm tone
• an audience you want to address affectionately

So the word can sound literal or symbolic, depending on who is being addressed.