Te echo muchísimo de menos.

Because te means you and functions as the object of the verb phrase.

In Te echo muchísimo de menos, the speaker is saying I miss you very much, so Spanish needs to show who is being missed:

• te = you (informal singular)
• echo de menos = I miss

So:

• Te echo de menos = I miss you
• Echo de menos a Marta = I miss Marta

Without te, the sentence would just mean I miss (someone/something), but it would not say whom.

Literally, it is not something that maps neatly onto natural English. The expression echar de menos is an idiom meaning to miss someone or something.

If you try to translate it word by word:

• echo = I throw / I cast / I put
• de menos = not very transparent on its own here

But as a whole, echar de menos simply means to miss.

The key point is: learn echar de menos as a fixed expression, not as separate words with a literal English equivalent.

Good question — these are two different words:

• echo = I throw / I miss here, from the verb echar
• hecho = done / made, or the noun fact, from the verb hacer

So in this sentence:

• Te echo de menos uses echo from echar

Examples:

• Echo la carta al buzón. = I post/put the letter in the mailbox.
• Está hecho. = It’s done.

This spelling difference is very important because echo and hecho sound the same in most accents, but they mean different things.

Muchísimo means very much, so much, or a lot.

So:

• Te echo de menos = I miss you
• Te echo muchísimo de menos = I miss you very, very much

It adds strong emotional emphasis.

Other possibilities:

• Te echo mucho de menos. = I miss you a lot
• Te echo muchísimo de menos. = I miss you very much / I miss you so much

Both are natural. Muchísimo is just stronger.

Yes, absolutely. That is completely natural.

You can think of it like this:

• mucho = a lot
• muchísimo = very, very much / so much

So both are correct:

• Te echo mucho de menos.
• Te echo muchísimo de menos.

The second one is simply more intense and emotional.

Because object pronouns like me, te, lo, la, nos, os, los, las usually go before a conjugated verb in Spanish.

So:

• Te echo de menos
• La veo
• Nos llama

That is the normal position.

With infinitives, gerunds, and affirmative commands, pronouns can attach to the end instead, but not here because echo is a conjugated verb in a normal statement.

Yes — echar de menos is especially common in Spain.

In many parts of Latin America, people often use:

• extrañar = to miss

So:

• Spain: Te echo de menos
• Many Latin American countries: Te extraño

Both mean I miss you, but Te echo de menos sounds especially Peninsular/Spain Spanish, which fits your sentence.

Not necessarily. It can be romantic, but it does not have to be.

You can say it to:

• a partner
• a family member
• a close friend
• even sometimes someone you are emotionally close to in general

What makes it sound stronger is muchísimo, so it is warm and heartfelt. Whether it sounds romantic depends on who says it to whom and the context.

Yes. Echar de menos can be used for both people and things.

Examples:

• Te echo de menos. = I miss you.
• Echo de menos mi casa. = I miss my home.
• Echo de menos el verano. = I miss summer.
• Echo de menos a mis amigos. = I miss my friends.

So it is a general verb expression for missing someone or something.

You change the verb and pronoun as needed.

Examples:

• Te echo muchísimo de menos. = I miss you very much (informal singular)
• Te echamos muchísimo de menos. = We miss you very much
• Os echo muchísimo de menos. = I miss you all very much (informal plural, common in Spain)
• Os echamos muchísimo de menos. = We miss you all very much

For formal you:

• Le echo muchísimo de menos. = I miss you very much (formal singular, less common in everyday intimate contexts)
• Les echo muchísimo de menos. = I miss you all very much (formal plural)

In Spain, os is important because it is the normal informal plural you all.

Because the personal a is used before a full noun or stressed pronoun, not before an object pronoun like te.

Compare:

• Echo de menos a Marta.
• Echo de menos a mis padres.
• Te echo de menos.

So when you use the pronoun te, you do not add a.

No, that would be incorrect.

The natural order is:

• Te echo muchísimo de menos

The pronoun te must go before the conjugated verb echo.

You may sometimes move muchísimo for stylistic emphasis in speech or writing, but the core structure stays the same:

• Te echo muchísimo de menos. = standard and natural
• Te echo de menos muchísimo. = possible, but less neutral and less common

For learners, the best pattern to remember is:

object pronoun + echar + de menos

A few common options are:

• Te eché muchísimo de menos. = I missed you very much
• Te he echado muchísimo de menos. = I’ve missed you very much / I have missed you very much
• Te echaba muchísimo de menos. = I used to miss you very much / I was missing you very much

Very roughly:

• eché = a completed past event
• he echado = present relevance, very common in Spain
• echaba = ongoing, repeated, or background feeling in the past

So if you are learning Spain Spanish, Te he echado muchísimo de menos is especially useful in everyday conversation, for example when someone has just returned.

Yes — that is the best approach.

Memorize:

• echar de menos = to miss
• Te echo de menos = I miss you
• Te echo muchísimo de menos = I miss you very much

It behaves like an idiomatic unit, so it is more useful to learn it as a whole than to try to build it word by word from English.