(a) At option of importer—(1) Filing. Except as provided in § 142.13, the importer may file the entry summary documentation at the time of entry in which case the entry summary, with estimated duties attached, shall serve as both the entry and the entry summary.
(2) Submission for preliminary review. If the importer intends to file the entry summary documentation at the time of entry, he may submit the entry summary documentation for preliminary review before arrival of the merchandise, in accordance with § 141.63(a) of this chapter. After preliminary review is completed, the entry summary shall be returned to the importer for filing in accordance with paragraph (a)(1) of this section.
(b) When required. If the importer is not required to file the entry summary documentation at the time of entry under the provisions of § 142.13, or if he does not elect to do so, the entry summary documentation shall be filed, with estimated duties attached, within 10 working days after the time of entry.
(c) Estimated duties. Estimated duties, if any, shall be deposited in accordance with the provisions of subpart G of part 141 of this chapter.