# 19 CFR § 145.1: Definitions

> Federal · Regulations · In force

URL: https://www.frixlaw.com/law-library/statutes/ecfr-19-145.1

## Section

- **Citation:** 19 CFR § 145.1
- **Heading:** Definitions
- **Jurisdiction:** Federal
- **Kind:** Regulations
- **Status:** In force
- **Text as of:** September 22, 2026
- **Source:** Publisher's official text
- **Location:** Title 19—Customs Duties > CHAPTER I—U.S. CUSTOMS AND BORDER PROTECTION, DEPARTMENT OF HOMELAND SECURITY › DEPARTMENT OF THE TREASURY > PART 145—MAIL IMPORTATIONS > Subpart A—General Provisions

## Text

(a) Mail article. “Mail article” means any posted parcel, packet, package, envelope, letter, aerogramme, box, card, or similar article or container, or any contents thereof, which is transmitted in mail subject to customs examination.
(b) Letter class mail. “Letter class mail” means any mail article, including packages, post cards, and aerogrammes, mailed at the letter rate or equivalent class or category of postage.
(c) Sealed letter class mail. “Sealed letter class mail” means letter class mail sealed against postal inspection by the sender.
[T.D. 78-102, 43 FR 14454, Apr. 6, 1978]

## Nearby sections

- [19 CFR § 145.1 § 145.1 Definitions.](https://www.frixlaw.com/law-library/statutes/ecfr-19-145.1.md)
- [19 CFR § 145.2 § 145.2 Mail subject to Customs examination.](https://www.frixlaw.com/law-library/statutes/ecfr-19-145.2.md)
- [19 CFR § 145.3 § 145.3 Opening of letter class mail; reading of correspondence prohibited.](https://www.frixlaw.com/law-library/statutes/ecfr-19-145.3.md)
- [19 CFR § 145.4 § 145.4 Dutiable merchandise without declaration or invoice, prohibited merchandise, and merchandise imported contrary to law.](https://www.frixlaw.com/law-library/statutes/ecfr-19-145.4.md)
- [19 CFR § 145.5 § 145.5 Undeliverable packages.](https://www.frixlaw.com/law-library/statutes/ecfr-19-145.5.md)
- [19 CFR § 145.11 § 145.11 Declarations of value and invoices.](https://www.frixlaw.com/law-library/statutes/ecfr-19-145.11.md)
- [19 CFR § 145.12 § 145.12 Entry of merchandise.](https://www.frixlaw.com/law-library/statutes/ecfr-19-145.12.md)
- [19 CFR § 145.13 § 145.13 Internal revenue tax on mail entries.](https://www.frixlaw.com/law-library/statutes/ecfr-19-145.13.md)
- [19 CFR § 145.14 § 145.14 Marking requirements.](https://www.frixlaw.com/law-library/statutes/ecfr-19-145.14.md)
- [19 CFR § 145.15 § 145.15 Bonding requirements for informal mail entries.](https://www.frixlaw.com/law-library/statutes/ecfr-19-145.15.md)
- [19 CFR § 145.21 § 145.21 Administrative review.](https://www.frixlaw.com/law-library/statutes/ecfr-19-145.21.md)
- [19 CFR § 145.22 § 145.22 Procedures for obtaining administrative review.](https://www.frixlaw.com/law-library/statutes/ecfr-19-145.22.md)
- [19 CFR § 145.23 § 145.23 Time limits.](https://www.frixlaw.com/law-library/statutes/ecfr-19-145.23.md)
- [19 CFR § 145.24 § 145.24 Amendment of entry.](https://www.frixlaw.com/law-library/statutes/ecfr-19-145.24.md)

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Source: Frix Law Library, https://www.frixlaw.com/law-library/statutes/ecfr-19-145.1. Check the current official text before relying on it. Not legal advice.