delivered the opinion of the Court.
Petitioner brought this action in Colorado state court to recover employment compensation allegedly due. Respondent removed the case to the United States District Court for the District of Colorado on the basis of diversity of citizenship. 28 U. S. C. §§ 1332, 1441. A jury awarded petitioner a verdict of $5,000 (considerably less than had been sought), and judgment was entered on March 26, 1984. Petitioner timely filed new-trial motions, challenging various rulings by the District Court, and a motion for attorney’s fees. (Colorado law provides that in a suit to collect compensation due from employment “the judgment. . . shall include a reasonable attorney fee in favor of the winning party, to be taxed as part of the costs of the action.” Colo. Rev. Stat. 8-4-114 (1986).) On May 14, 1984, the District Court denied the new-trial motions, found that petitioner was entitled to attorney’s fees, and requested further briefing and documentation before de *198 termining their amount. The District Court issued its final order concerning the attorney’s fees on August 1, 1984. On August 29, petitioner filed notice of appeal to the Court of Appeals for the Tenth Circuit, covering all the District Court’s post-trial orders.
Respondent filed a motion to dismiss the appeal, arguing that the judgment was final and immediately appealable when the order denying the new-trial motions was entered May 14, 1984, and that the notice of appeal was not filed within 30 days of that order as required by Federal Rules of Appellate Procedure 4(a)(1) and (4). The Court of Appeals granted the motion to dismiss as to all issues except the award of attorney’s fees, which it affirmed. We granted certiorari,
It is common ground in this case that if the District Court’s decision on the merits was appealable before its determination of attorney’s fees, then the merits appeal was untimely. See Fed. Rules App. Proc. 4(a)(1), (4), (6); Fed. Rules Civ. Proc. 54(a), 58. Petitioner contends that Colorado law governs this question and that “[u]nder Colorado law a claim is not final and appealable until attorneys fees are fully determined.” Brief for Petitioner 13. We do not agree that Colorado law governs.
Although state law generally supplies the rules of decision in federal diversity cases, see 28 U. S. C. § 1652;
Erie R. Co.
v.
Tompkins,
The question before us, therefore, is whether a decision on the merits is a “final decision” as a matter of federal law under § 1291 when the recoverability or amount of attorney’s fees for the litigation remains to be determined. “A ‘final decision’ generally is one which ends the litigation on the merits and leaves nothing for the court to do but execúte the judgment.”
Catlin
v.
United States,
The foregoing discussion is ultimately question-begging, however, since it assumes that the order to which the fee issue was collateral
was
an order ending litigation on the merits. If one were to regard the demand for attorney’s fees as
itself
part of the merits, the analysis would not apply. The merits would then not have been concluded, and § 1291 finality would not exist. See
Liberty Mutual Insurance Co.
v.
Wetzel,
Petitioner contends, however, that the general status of attorney’s fees for § 1291 purposes must be altered when the statutory or decisional law authorizing them makes plain (as he asserts Colorado law does) that they are to be part of the merits judgment. This proposition is not without some support. Some Courts of Appeals have held that the statutes creating liability for attorney’s fees can cause them to be part of the merits relief for purposes of §1291. See,
e. g., Holmes
v.
J. Ray McDermott & Co.,
We have said elsewhere that “[t]he considerations that determine finality are not abstractions but have reference to very real interests — not merely those of the immediate parties, but, more particularly, those that pertain to the smooth functioning of our judicial system.”
Republic Natural Gas Co.
v.
Oklahoma,
For all practical purposes an appeal of merits-without-attorney’s-fees when there is a statute deeming the attorney’s fees to be part of the merits is no more harmful to the trial process than an appeal of merits-without-attorney’s-fees when there is no such statute. That “deeming” does not render the appeal more disruptive of ongoing proceedings, more likely to eliminate a trial judge’s opportunity for reconsideration, more susceptible to being mooted by settlement, or in any way (except nominally) a more piecemeal enterprise. In short, no interest pertinent to § 1291 is served by according different treatment to attorney’s fees deemed part of the merits recovery; and a significant interest is disserved. The time of appealability, having jurisdictional consequences, should above all be clear. We are not inclined to adopt a disposition that requires the merits or nonmerits status of each attorney’s fee provision to be clearly established before the time to appeal can be clearly known. Courts and litigants are best served by the bright-line rule, which accords with traditional understanding, that a decision on the merits is a “final decision” for purposes of §1291 whether or not *203 there remains for adjudication a request for attorney’s fees attributable to the case.
Finally, petitioner argues that even if the Court of Appeals properly decided the question of appealability, the decision constitutes a significant change in the law and therefore should only be applied prospectively.. Regardless of whether today’s decision works a change, our cases hold that “[a] court lacks discretion to consider the merits of a case over which it is without jurisdiction, and thus, by definition, a jurisdictional ruling may never be made prospective only.”
Firestone Tire & Rubber Co.
v.
Risjord,
* * *
The Tenth Circuit correctly concluded that federal law governed the question of appealability and that petitioner’s judgment on the merits was final and appealable when entered. Accordingly, its judgment is
Affirmed.
