Meu pai é titular depois da troca de titularidade.

Not exactly. In Brazilian Portuguese, titular usually means the official holder of something like:

• a phone line
• a utility account
• a bank account
• a subscription
• a contract

So in this sentence, meu pai é titular means your father is now the registered account holder / official holder.

It may overlap with owner in some contexts, but titular is often more about the name officially attached to the service or contract than about legal ownership in a broad sense.

Titularidade is a noun meaning holder status, ownership status, or more naturally in this context, account ownership / registration in someone’s name.

So:

• titular = the holder
• titularidade = the status/condition of being the holder

Troca de titularidade is a very common fixed expression in Brazil, especially for utilities and service accounts. It means something like:

• change of account holder
• transfer of ownership/name on the account

Using troca de titular would sound less natural in this kind of administrative context.

Because depois normally takes the preposition de before a noun phrase.

So the structure is:

• depois de
  • noun

Examples:

• depois da aula = after class
• depois do almoço = after lunch
• depois da troca de titularidade = after the change of account holder

Here, de + a becomes da:

• depois de a troca → depois da troca

Da is a contraction of:

• de + a = da

In this sentence:

• depois da troca = after the change
• literally: after of the change

You will see these contractions constantly in Portuguese:

• de + o = do
• de + a = da
• em + o = no
• em + a = na

So da troca is completely normal and required here.

Because titular is being used as a predicate noun after ser, describing your father’s role or status.

Compare:

• Meu pai é médico. = My father is a doctor.
• Meu pai é titular. = My father is the holder.

Portuguese often omits the article in this kind of structure when talking about profession, role, identity, or status.

If you said Meu pai é o titular, that would usually mean My father is the holder/the one who is the holder, with more emphasis on identifying him as a specific person.

So:

• é titular = he is a holder / he is the official holder
• é o titular = he is the holder, specifically the one in question

É is the third-person singular form of ser in the present tense:

• eu sou
• você/ele/ela é
• nós somos
• eles/elas são

Since meu pai = my father = he, the correct form is é.

The sentence is stating a fact or status:

• Meu pai é titular = My father is the holder

Because titular here describes a more stable or official status, not a temporary condition.

In Portuguese:

• ser is used for identity, classification, role, and official status
• estar is used for temporary states, location, or conditions

So:

• Meu pai é titular = My father is the official holder
• using estar titular would sound wrong here

This is similar to:

• Ela é gerente. = She is a manager.
• Ele é o responsável pela conta. = He is the person responsible for the account.

Yes. It tells you when the first part is true.

The sentence breaks down like this:

• Meu pai é titular = My father is the holder
• depois da troca de titularidade = after the transfer/change of account holder

So the second part is a time phrase that situates the event or status.

In natural English, you might think of it as:

• My father is the account holder after the account-holder transfer or more naturally:
• After the transfer, my father is the account holder

It may feel repetitive to an English speaker, but it is normal in Portuguese because the two words are doing different jobs:

• titular = the holder
• titularidade = holder status / account ownership status

So the sentence is not clumsy in Portuguese administrative language. In fact, it sounds quite standard, especially in customer service, legal, banking, telecom, and utility contexts.

This kind of repetition is common in formal Portuguese when related words are used together.

Yes. A very natural alternative is:

• Depois da troca de titularidade, meu pai é titular.

That puts the time expression first:

• After the transfer of account holder status, my father is the holder.

However, depending on context, a Brazilian speaker might choose an even more natural version such as:

• Depois da troca de titularidade, meu pai fica como titular.
• Depois da troca de titularidade, meu pai passa a ser o titular.

These can sound more natural when talking about a change that results in a new official holder.

It is understandable, but it sounds somewhat administrative or formal because of troca de titularidade.

In real life, Brazilians might say:

• Depois da troca de titularidade, meu pai vai ficar como titular.
• Meu pai vai ser o titular depois da troca.
• Depois da transferência, a conta vai ficar no nome do meu pai.

That last one is especially common in everyday speech:

• A conta vai ficar no nome do meu pai. = The account will be in my father’s name.

So your original sentence is correct and understandable, but it has a more official/document-style tone.

Meu means my. It is a possessive adjective and agrees with the noun it modifies.

Since pai is masculine singular, we use:

• meu pai = my father

Other forms include:

• minha mãe = my mother
• meus pais = my parents
• minhas irmãs = my sisters

So meu changes depending on the gender and number of the noun that follows.

A broad approximate pronunciation is:

meh-ooh pah-ee eh tee-too-LAR deh-POYJ dah TRO-kah jee chee-too-lah-ree-DA-jee

A few helpful notes:

• meu often sounds like meh-ooh in approximation
• pai sounds like pie
• titular has stress on the last syllable: ti-tu-LAR
• depois in many Brazilian accents sounds roughly like deh-POYS or deh-POYJ
• de titularidade may sound like jee chee-too-lah-ree-DA-jee in some accents because d and t can soften before i

Exact pronunciation varies by region, but that gives you a useful starting point.