Tiedoksianto saapui sähköpostitse.

Tiedoksianto is more formal than an everyday message. It usually means an official notification, formal notice, or service of notice/document in administrative or legal language.

It comes from:

• tieto = information, knowledge
• antaa = to give

So the idea is something like giving information officially.

In normal everyday Finnish, people would more often say things like:

• viesti = message
• ilmoitus = announcement, notice

But tiedoksianto sounds bureaucratic or official.

Saapui is the simple past tense (imperfect) of saapua = to arrive.

Forms:

• saapua = to arrive
• saapuu = arrives / is arriving
• saapui = arrived
• saapunut = arrived (past participle), not the normal finite verb form here

So in this sentence:

• Tiedoksianto saapui sähköpostitse.
• The notification arrived by email.

A few examples:

• Kirje saapui eilen. = The letter arrived yesterday.
• Paketti saapuu huomenna. = The package arrives tomorrow.

The ending -itse often expresses by, via, or through the means of something.

So:

• sähköposti = email
• sähköpostitse = by email / via email

This form is somewhat formal or written in style, and it is especially common in official language.

Other examples:

• puhelimitse = by phone
• kirjeitse = by letter
• internetitse = via the internet

So sähköpostitse tells you the means/method by which the notification arrived.

Yes, in many situations you could say sähköpostilla, and it would usually be understood as by email.

However, there is a style difference:

• sähköpostitse = more formal, administrative, official
• sähköpostilla = more everyday, conversational

So:

• Tiedoksianto saapui sähköpostitse. sounds natural in official language.
• Viesti tuli sähköpostilla. sounds more everyday.

Both can refer to the method, but -itse often feels especially suitable in formal notices and documents.

Finnish does not have articles like English a/an and the.

So tiedoksianto can mean:

• a notification
• the notification

Which one is intended depends on context.

In this sentence, English would often use the if both speakers already know which notification is being talked about:

• The notification arrived by email.

But Finnish does not need a separate word for that.

Yes, Finnish word order is fairly flexible, though different orders change the emphasis.

The neutral order here is:

• Tiedoksianto saapui sähköpostitse.
• subject + verb + method

Possible alternatives:

• Sähköpostitse saapui tiedoksianto.
  • emphasizes by email
• Saapui tiedoksianto sähköpostitse.
  • possible, but less neutral and more context-dependent

The original sentence is a straightforward, neutral way to say it.

Mostly yes, but in Finnish saapua is often a bit more formal than some everyday alternatives.

Here:

• tiedoksianto saapui = the notification arrived

For everyday speech, people might also use:

• tulla = to come

For example:

• Viesti tuli sähköpostilla. = The message came by email.

So saapua is perfectly correct, but it often sounds a little more formal or official than tulla.

Because tiedoksianto is the subject of the sentence, and the subject is often in the nominative (basic dictionary form).

Structure:

• Tiedoksianto = subject
• saapui = verb
• sähköpostitse = adverbial expression of method

So the sentence literally works like:

• [The notification] [arrived] [by email].

Not in the same way as the most common Finnish cases like:

• nominative
• genitive
• partitive
• inessive
• elative, etc.

The ending -itse is often treated as an old adverbial/instrumental-type ending rather than one of the central productive case endings learners first study.

The important thing for a learner is this:

• forms ending in -itse often function like adverbs meaning by means of / via
• they are common in formal written Finnish

So it is best to learn sähköpostitse, puhelimitse, and similar forms as useful set expressions.

Depending on context and translation style, yes. A very natural English rendering might be:

• The notice was delivered by email.
• The notification arrived by email.

Finnish uses saapui literally meaning arrived, but in official English, was delivered may sometimes sound more natural if the point is the method of delivery.

So the Finnish focuses on the notification reaching someone, while English might express that in more than one way.

It is grammatically natural, but stylistically it sounds formal and official, not very conversational.

Why?

• tiedoksianto is formal
• saapui is slightly formal
• sähköpostitse is also formal

A more everyday version might be:

• Ilmoitus tuli sähköpostilla.
• Viesti tuli sähköpostiin.
  (though this can shift the meaning slightly depending on context)

So the original sentence feels like something from a legal, administrative, or institutional context.

They express different ideas:

• sähköpostitse = by email / via email
  → focuses on the method
• sähköpostiin = into the email / to the email account/inbox
  → focuses on the destination

Compare:

• Tiedoksianto saapui sähköpostitse. = The notification arrived by email.
• Viesti tuli sähköpostiin. = The message came to the email inbox/account.

So -itse answers how?, while -iin answers to where?