noun
declarant; filer; reporter
Refers to a person who submits a formal declaration, report, or filing, especially in legal, tax, or customs contexts.
税関で申告者は所持品をすべて申告しなければならない。
At customs, the declarant must declare all belongings.
確定申告の申告者は期限内に書類を提出する必要がある。
The filer of a tax return must submit the documents by the deadline.