The Harmonized Tariff Schedule of the United States authorizes the United States Customs Service to classify and fix the rate of duty on imports, under rules and regulations issued by the Secretary of the Treasury. As relevant here, the Secretary provides for tariff rulings before the entry of goods by regulations authorizing "ruling letters" setting tariff classifications for particular imports. Any of the 46 port-of-entry Customs offices and the Customs Headquarters Office may issue such letters. Respondent imports "day planners," three-ring binders with pages for daily schedules, phone numbers and addresses, a calendar, and suchlike. After classifying the planners as duty-free for several years, Customs Headquarters issued a ruling letter classifying them as bound diaries subject to tariff. Mead filed suit in the Court of International Trade, which granted the Government summary judgment. In reversing, the Federal Circuit found that ruling letters should not be treated like Customs regulations, which receive the highest level of deference under Chevron U. S. A. Inc. v. Natural Resources Defense Council, Inc., 467 U. S. 837, because they are not preceded by notice and comment as under the Administrative Procedure Act (APA), do not carry the force of law, and are not intended to clarify importers's rights and obligations beyond the specific case. The court gave no deference at all to the ruling letter at issue.
Held: Administrative implementation of a particular statutory provision qualifies for Chevron deference when it appears that Congress delegated authority to the agency generally to make rules carrying the force of law, and that the agency interpretation claiming deference was promulgated in the exercise of such authority. Such delegation may be shown in a variety of ways, as by an agency's power to engage in adjudication or notice-and-comment rulemaking, or by some other indication of comparable congressional intent. A Customs ruling letter has no claim to Chevron deference, but, under Skidmore v. Swift & Co., 323 U. S. 134, it is eligible to claim respect according to its persuasiveness. Pp. 7-19.
(a) When Congress has explicitly left a gap for an agency to fill, there has been any express delegation of authority to the agency to elucidate a specific statutory provision by regulation, and any ensuing regulation is binding unless procedurally defective, arbitrary or capricious in substance, or manifestly contrary to the statute. Even in the absence of an express delegation of authority on a particular question, agencies charged with applying a statute necessarily make all sorts of interpretive choices, and while not all of those choices bind judges to follow them, they may influence courts facing questions the agencies have already answered. The weight accorded to an administrative judgment "will depend upon the thoroughness evident in its consideration, the validity of its reasoning, its consistency with earlier and later pronouncements, and all those factors which give it power to persuade, if lacking power to control." Skidmore, supra, at 140. In Chevron, this Court identified a category of interpretive choices distinguished by an additional reason for judicial deference, recognizing that Congress engages not only in express, but also in implicit, delegation of specific interpretive authority. It can be apparent from the agency's generally conferred authority and other statutory circumstances that Congress would expect the agency to be able to speak with the force of law when addressing ambiguity in the statute or fills in a space in the enacted law, even one about which Congress did not have intent as to a particular result. When circumstances implying such an expectation exist, a reviewing court must accept the agency's position if Congress has not previously spoken to the point at issue and the agency's interpretation is reasonable. A very good indicator of delegation meriting Chevron treatment is express congressional authorizations to engage in the rulemaking or adjudication process that produces the regulations or rulings for which deference is claimed. Thus, the overwhelming number of cases applying Chevron deference have reviewed the fruits of notice-and-comment rulemaking or formal adjudication. Although the fact that the tariff classification at issue was not a product of such formal process does not alone bar Chevron's application, cf., e.g., NationsBank of N. C., N. A. v. Variable Annuity Life Ins. Co.,
The opinion of the court was delivered by: Justice Souter
On Writ Of Certiorari To The United States Court Of Appeals For The Federal Circuit
The question is whether a tariff classification ruling by the United States Customs Service deserves judicial deference. The Federal Circuit rejected Customs's invocation of Chevron U. S. A. Inc. v. Natural Resources Defense Council, Inc., 467 U. S. 837 (1984), in support of such a ruling, to which it gave no deference. We agree that a tariff classification has no claim to judicial deference under Chevron, there being no indication that Congress intended such a ruling to carry the force of law, but we hold that under Skidmore v. Swift & Co., 323 U. S. 134 (1944), the ruling is eligible to claim respect according to its persuasiveness.
Imports are taxed under the Harmonized Tariff Schedule of the United States (HTSUS), 19 U. S. C. §1202. Title 19 U. S. C. §1500(b) provides that Customs "shall, under rules and regulations prescribed by the Secretary [of the Treasury] ... fix the final classification and rate of duty applicable to ... merchandise" under the HTSUS. Section 1502(a) provides that
"[t]he Secretary of the Treasury shall establish and promulgate such rules and regulations not inconsistent with the law (including regulations establishing procedures for the issuance of binding rulings prior to the entry of the merchandise concerned), and may disseminate such information as may be necessary to secure a just, impartial, and uniform appraisement of imported merchandise and the classification and assessment of duties thereon at the various ports of entry." *fn1 See also §1624 (general delegation to Secretary to issue rules and regulations for the admission of goods).
The Secretary provides for tariff rulings before the entry of goods by regulations authorizing "ruling letters" setting tariff classifications for particular imports. 19 CFR §177.8 (2000). A ruling letter
"represents the official position of the Customs Service with respect to the particular transaction or issue described therein and is binding on all Customs Service personnel in accordance with the provisions of this section until modified or revoked. In the absence of a change of practice or other modification or revocation which affects the principle of the ruling set forth in the ruling letter, that principle may be cited as authority in the disposition of transactions involving the same circumstances." §177.9(a).
After the transaction that gives it birth, a ruling letter is to "be applied only with respect to transactions involving articles identical to the sample submitted with the ruling request or to articles whose description is identical to the description set forth in the ruling letter." §177.9(b)(2). As a general matter, such a letter is "subject to modification or revocation without notice to any person, except the person to whom the letter was addressed," §177.9(c), and the regulations consequently provide that "no other person should rely on the ruling letter or assume that the principles of that ruling will be applied in connection with any transaction other than the one described in the letter," ibid. Since ruling letters respond to transactions of the moment, they are not subject to notice and comment before being issued, may be published but need only be made "available for public inspection," 19 U. S. C. §1625(a), and, at the time this action arose, could be modified without notice and comment under most circumstances, 19 CFR §177.10(c) (2000).*fn2 A broader notice-and-comment requirement for modification of prior rulings was added by statute in 1993, Pub. L. 103-182 §623, 107 Stat. 2186, codified at 19 U. S. C. §1625(c), and took effect after this case arose.*fn3
Any of the 46 *fn4 port-of-entry *fn5 Customs offices may issue ruling letters, and so may the Customs Headquarters Office, in providing "[a]dvice or guidance as to the interpretation or proper application of the Customs and related laws with respect to a specific Customs transaction [which] may be requested by Customs Service field offices ... at any time, whether the transaction is prospective, current, or completed," 19 CFR §177.11(a) (2000). Most ruling letters contain little or no reasoning, but simply describe goods and state the appropriate category and tariff. A few letters, like the Headquarters ruling at issue here, set out a rationale in some detail.
Respondent, the Mead Corporation, imports "day planners," three-ring binders with pages having room for notes of daily schedules and phone numbers and addresses, together with a calendar and suchlike. The tariff schedule on point falls under the HTSUS heading for "[r]egisters, account books, notebooks, order books, receipt books, letter pads, memorandum pads, diaries and similar articles," HTSUS subheading 4820.10, which comprises two subcategories. Items in the first, "[d]iaries, notebooks and address books, bound; memorandum pads, letter pads and similar articles," were subject to a tariff of 4.0% at the time in controversy. 185 F. 3d 1304, 1305 (CA Fed. 1999) (citing subheading 4820.10.20); see also App. to Pet. for Cert. 46a. Objects in the second, covering "[o]ther" items, were free of duty. HTSUS subheading 4820.10.40; see also App. to Pet. for Cert. 46a.
Between 1989 and 1993, Customs repeatedly treated day planners under the "other" HTSUS subheading. In January 1993, however, Customs changed its position, and issued a Headquarters ruling letter classifying Mead's day planners as "Diaries ..., bound" subject to tariff under subheading 4820.10.20. That letter was short on explanation, App. to Brief in Opposition 4a-6a, but after Mead's protest, Customs Headquarters issued a new letter, carefully reasoned but never published, reaching the same conclusion, App. to Pet. for Cert. 28a-47a. This letter considered two definitions of "diary" from the Oxford English Dictionary, the first covering a daily journal of the past day's events, the second a book including " `printed dates for daily memoranda and jottings; also ... calendars ... .' " Id., at 33a-34a (quoting Oxford English Dictionary 321 (Compact ed. 1982)). Customs concluded that "diary" was not confined to the first, in part because the broader definition reflects commercial usage and hence the "commercial identity of these items in the marketplace." App. to Pet. for Cert. 34a. As for the definition of "bound," Customs concluded that HTSUS was not referring to "bookbinding," but to a less exact sort of fastening described in the Harmonized Commodity Description and Coding System Explanatory Notes to Heading 4820, which spoke of binding by " `reinforcements or fittings of metal, plastics, etc.' " Id., at 45a.
Customs rejected Mead's further protest of the second Headquarters ruling letter, and Mead filed suit in the Court of International Trade (CIT). The CIT granted the Government's motion for summary judgment, adopting Customs's reasoning without saying anything about deference. 17 F. Supp. 2d 1004 (1998).
Mead then went to the United States Court of Appeals for the Federal Circuit. While the case was pending there this Court decided United States v. Haggar Apparel Co., 526 U. S. 380 (1999), holding that Customs regulations receive the deference described in Chevron U. S. A. Inc. v. Natural Resources Defense Council, Inc., 467 U. S. 837 (1984). The appeals court requested briefing on the impact of Haggar, and the Government argued that classification rulings, like Customs regulations, deserve Chevron deference.
The Federal Circuit, however, reversed the CIT and held that Customs classification rulings should not get Chevron deference, owing to differences from the regulations at issue in Haggar. Rulings are not preceded by notice and comment as under the Administrative Procedure Act (APA), 5 U. S. C. §553, they "do not carry the force of law and are not, like regulations, intended to clarify the rights and obligations of importers beyond the specific case under review." 185 F. 3d, at 1307. The appeals court thought classification rulings had a weaker Chevron claim even than Internal Revenue Service interpretive rulings, to which that court gives no deference; unlike rulings by the IRS, Customs rulings issue from many locations and need not be published. 185 F. 3d, at 1307-1308.
The Court of Appeals accordingly gave no deference at all to the ruling classifying the Mead day planners and rejected the agency's reasoning as to both "diary" and "bound." It thought that planners were not diaries because they had no space for "relatively extensive notations about events, observations, feelings, or thoughts" in the past. Id., at 1310. And it concluded that diaries "bound" in subheading 4810.10.20 presupposed "unbound" diaries, such that treating ring-fastened diaries as "bound" would leave the "unbound diary" an empty category. Id., at 1311.
We granted certiorari, 530 U. S. 1202 (2000), in order to consider the limits of Chevron deference owed to administrative practice in applying a statute. We hold that administrative implementation of a particular statutory provision qualifies for Chevron deference when it appears that Congress delegated authority to the agency generally to make rules carrying the force of law, and that the agency interpretation claiming deference was promulgated in the exercise of that authority. Delegation of such authority may be shown in a variety of ways, as by an agency's power to engage in adjudication or notice-and-comment rulemaking, or by some other indication of a comparable congressional intent. The Customs ruling at issue here fails to qualify, although the possibility that it deserves some deference under Skidmore leads us to vacate and remand.
When Congress has "explicitly left a gap for an agency to fill, there is an express delegation of authority to the agency to elucidate a specific provision of the statute by regulation," Chevron, 467 U. S., at 843-844, and any ensuing regulation is binding in the courts unless procedurally defective, arbitrary or capricious in substance, or manifestly contrary to the statute.*fn6 See id., at 844; United States v. Morton, 467 U. S. 822, 834 (1984); APA, 5 U. S. C. §§706(2)(A), (D). But whether or not they enjoy any express delegation of authority on a particular question, agencies charged with applying a statute necessarily make all sorts of interpretive choices, and while not all of those choices bind judges to follow them, they certainly may influence courts facing questions the agencies have already answered. "[T]he well-reasoned views of the agencies implementing a statute `constitute a body of experience and informed judgment to which courts and litigants may properly resort for guidance,' " Bragdon v. Abbott, 524 U. S. 624, 642 (1998) (quoting Skidmore, 323 U. S., at 139-140), and "[w]e have long recognized that considerable weight should be accorded to an executive department's construction of a statutory scheme it is entrusted to administer ... ." Chevron, supra, at 844 (footnote omitted); see also Ford Motor Credit Co. v. Milhollin, 444 U. S. 555, 565 (1980); Zenith Radio Corp. v. United States, 437 U. S. 443, 450 (1978). The fair measure of deference to an agency administering its own statute has been understood to vary with circumstances, and courts have looked to the degree of the agency's care,*fn7 its consistency,*fn8 formality,*fn9 and relative expertness,*fn10 and to the persuasiveness of the agency's position, see Skidmore, supra, at 139-140. The approach has produced a spectrum of judicial responses, from great respect at one end, see, e.g., Aluminum Co. of America v. Central Lincoln Peoples' Util. Dist., 467 U. S. 380, 389-390 (1984) (" `substantial deference' " to administrative construction), to near indifference at the other, see, e.g., Bowen v. Georgetown Univ. Hospital, 488 U. S. 204, 212-213 (1988) (interpretation advanced for the first time in a litigation brief). Justice Jackson summed things up in Skidmore v. Swift & Co.:
"The weight [accorded to an administrative] judgment in a particular case will depend upon the thoroughness evident in its consideration, the validity of its reasoning, its consistency with earlier and later pronouncements, and all those factors which give it power to persuade, if lacking power to control." 323 U. S., at 140.
Since 1984, we have identified a category of interpretive choices distinguished by an additional reason for judicial deference. This Court in Chevron recognized that Congress not only engages in express delegation of specific interpretive authority, but that "[s]ometimes the legislative delegation to an agency on a particular question is implicit." 467 U. S., at 844. Congress, that is, may not have expressly delegated authority or responsibility to implement a particular provision or fill a particular gap. Yet it can still be apparent from the agency's generally conferred authority and other statutory circumstances that Congress would expect the agency to be able to speak with the force of law when it addresses ambiguity in the statute or fills a space in the enacted law, even one about which "Congress did not actually have an intent" as to a particular result. Id., at 845. When circumstances implying such an expectation exist, a reviewing court has no business rejecting an agency's exercise of its generally conferred authority to resolve a particular statutory ambiguity simply because the agency's chosen resolution seems unwise, see id., at 845-846, but is obliged to accept the agency's position if Congress has not previously spoken to the point at issue and the agency's interpretation is reasonable, see id., at 842-845; cf. 5 U. S. C. §706(2) (a reviewing court shall set aside agency action, findings, and conclusions found to be "arbitrary, capricious, an abuse of discretion, or otherwise not in accordance with law").
We have recognized a very good indicator of delegation meriting Chevron treatment in express congressional authorizations to engage in the process of rulemaking or adjudication that produces regulations or rulings for which deference is claimed. See, e.g., EEOC v. Arabian American Oil Co., 499 U. S. 244, 257 (1991) (no Chevron deference to agency guideline where congressional delegation did not include the power to " `promulgate rules or regulations' " (quoting General Elec. Co. v. Gilbert, 429 U. S. 125, 141) (1976)); see also Christensen v. Harris County, 529 U. S. 576, 596-597 (2000) (Breyer, J., dissenting) (where it is in doubt that Congress actually intended to delegate particular interpretive authority to an agency, Chevron is "inapplicable"). It is fair to assume generally that Congress contemplates administrative action with the effect of law when it provides for a relatively formal administrative procedure tending to foster the fairness and deliberation that should underlie a pronouncement of such force.*fn11 Cf. Smiley v. Citibank (South Dakota), N. A., 517 U. S. 735, 741 (1996) (APA notice and comment "designed to assure due deliberation"). Thus, the overwhelming number of our cases applying Chevron deference have reviewed the fruits of notice-and-comment rulemaking or formal adjudication.*fn12 That said, and as significant as notice-and-comment is in pointing to Chevron authority, the want of that procedure here does not decide the case, for we have ...