keiyakusya ha seikyuubi, siharaikigen, getugakuryoukin, kouzahurikae, zimutesuuryou, tanmatudaikin wo kakuninsuru.

The sentence follows this pattern:

Topic + object list + verb

• 契約者 は = as for the subscriber / the contract holder
• 請求日、支払期限、月額料金、口座振替、事務手数料、端末代金 を = the billing date, payment deadline, monthly fee, bank transfer, administrative fee, and device cost
• 確認する = check / confirm

So structurally, it is:

The subscriber checks/confirms A, B, C, D, E, and F.

は marks the topic of the sentence: what the sentence is about.

So 契約者は means something like:

• As for the subscriber, ...
• The subscriber, ...

If you used が, it would sound more like you are specifically identifying the subscriber as the one who does the action, often with a stronger focus or contrast.

In a formal written sentence like this, は is very natural because the sentence is presenting a general statement about what the subscriber does or should do.

Because the entire list is treated as one combined object of the verb 確認する.

So:

• 請求日、支払期限、月額料金、口座振替、事務手数料、端末代金 を 確認する

means:

• check the billing date, payment deadline, monthly fee, bank transfer, administrative fee, and device cost

Japanese often puts the particle only once, after the final item in a list.

Yes, mostly.

The Japanese comma 、 is being used to separate items in a list, just like English commas:

• 請求日、支払期限、月額料金...

This is very common in written Japanese, especially in formal, informational, or business-style writing.

Japanese can list nouns in more than one way.

Using と is common when you want a straightforward A and B and C type list:

• 請求日と支払期限と月額料金...

But in formal writing, labels, instructions, and documents, it is very common to list items with commas alone:

• 請求日、支払期限、月額料金...

This gives the sentence a more official, checklist-like feel.

確認する is the dictionary form of the verb.

In Japanese, this form can express several things depending on context:

• a habitual action
• a future action
• a general statement
• an instruction-like statement in formal writing

So here it does not have to mean strictly present tense in the English sense. In a document, it can mean something like:

• The subscriber confirms ...
• The subscriber shall confirm ...
• The subscriber is to confirm ...

A polite version would be 確認します.

Not really. It sounds more like formal written Japanese, such as:

• a contract
• terms of service
• a guide
• a procedure manual
• a form or application explanation

Reasons it sounds formal:

• the long noun list
• the plain dictionary-form verb 確認する
• the business/legal vocabulary

In conversation, someone might say something more like:

• 請求日とか支払期限とかを確認してください。
• 契約者がこれらを確認します。

A natural reading is:

けいやくしゃ は せいきゅうび、しはらいきげん、げつがくりょうきん、こうざふりかえ、じむてすうりょう、たんまつだいきん を かくにんする。

Breakdown:

• 契約者 = けいやくしゃ
• 請求日 = せいきゅうび
• 支払期限 = しはらいきげん
• 月額料金 = げつがくりょうきん
• 口座振替 = こうざふりかえ
• 事務手数料 = じむてすうりょう
• 端末代金 = たんまつだいきん
• 確認する = かくにんする

Japanese often combines several kanji-based nouns into one compact compound noun.

For example:

• 月額料金 = monthly + amount + fee
• 事務手数料 = administrative/business + handling + fee
• 端末代金 = device/terminal + price

This is extremely common in formal and business Japanese. English often uses short phrases, but Japanese often packs the same idea into a single compound noun.

Because 月額料金 is a fixed compound noun, not a phrase built with の.

Japanese can express relationships between nouns in two main ways:

1. Compound noun
   • 月額料金
2. Noun + の + noun
   • something like 月額の料金

Both can exist in Japanese, but the compound form is often more concise and more natural in formal/business writing.

So 月額料金 sounds tighter and more standard here.

It can be either, depending on context.

Japanese nouns usually do not show singular/plural the way English does. So 契約者 could mean:

• the subscriber
• a subscriber
• subscribers
• the contract holder

In a document, it often refers generically to the subscriber / the customer / the person who signed the contract.

It is stronger than just look at.

確認する usually means:

• confirm
• check
• verify
• make sure of

So the idea is not merely to see the items, but to check them carefully.

In this sentence, the subscriber is expected to make sure the listed details are correct or understood.

Yes.

In formal Japanese, especially in documents and rules, the plain form can function like an instruction or requirement without using please language.

So depending on context, this could feel like:

• The subscriber checks the following items.
• The subscriber must confirm the following items.
• The subscriber should confirm the following items.

Japanese formal writing often leaves that nuance to the context rather than spelling it out with something like してください.

This is common in business and legal Japanese. The style is very compressed.

Instead of writing a full explanation for each item, the sentence simply lists key categories:

• billing date
• payment deadline
• monthly fee
• bank transfer
• administrative fee
• device cost

This creates a neat, official, document-like style. Japanese formal writing often prefers this compact noun-heavy structure.

Yes.

In a sentence like this, the listed nouns often function as checkpoints or information categories.

For example, 口座振替 may not just mean the abstract concept of bank transfer, but something like:

• the bank transfer arrangement
• whether payment is by bank withdrawal
• the bank account withdrawal details

That is very common in Japanese formal writing: a short noun can stand for the relevant information about that item.