diff --git a/CHANGELOG.md b/CHANGELOG.md
index 66b41ca77..be621e1eb 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -9,6 +9,7 @@
 - Enhance: リアクション・いいねの総数を表示するように
 - Enhance: リアクション受け入れが「いいねのみ」の場合はリアクション絵文字一覧を表示しないように
 - Fix: 一部のページ内リンクが正しく動作しない問題を修正
+- Fix: 周年の実績が閏年を考慮しない問題を修正
 
 ### Server
 -
diff --git a/packages/frontend/src/boot/main-boot.ts b/packages/frontend/src/boot/main-boot.ts
index 61f04678b..8016e8b0e 100644
--- a/packages/frontend/src/boot/main-boot.ts
+++ b/packages/frontend/src/boot/main-boot.ts
@@ -187,14 +187,26 @@ export async function mainBoot() {
 		if ($i.followersCount >= 500) claimAchievement('followers500');
 		if ($i.followersCount >= 1000) claimAchievement('followers1000');
 
-		if (Date.now() - new Date($i.createdAt).getTime() > 1000 * 60 * 60 * 24 * 365) {
-			claimAchievement('passedSinceAccountCreated1');
-		}
-		if (Date.now() - new Date($i.createdAt).getTime() > 1000 * 60 * 60 * 24 * 365 * 2) {
-			claimAchievement('passedSinceAccountCreated2');
-		}
-		if (Date.now() - new Date($i.createdAt).getTime() > 1000 * 60 * 60 * 24 * 365 * 3) {
+		const createdAt = new Date($i.createdAt);
+		const createdAtThreeYearsLater = new Date($i.createdAt);
+		createdAtThreeYearsLater.setFullYear(createdAtThreeYearsLater.getFullYear() + 3);
+		if (now >= createdAtThreeYearsLater) {
 			claimAchievement('passedSinceAccountCreated3');
+			claimAchievement('passedSinceAccountCreated2');
+			claimAchievement('passedSinceAccountCreated1');
+		} else {
+			const createdAtTwoYearsLater = new Date($i.createdAt);
+			createdAtTwoYearsLater.setFullYear(createdAtTwoYearsLater.getFullYear() + 2);
+			if (now >= createdAtTwoYearsLater) {
+				claimAchievement('passedSinceAccountCreated2');
+				claimAchievement('passedSinceAccountCreated1');
+			} else {
+				const createdAtOneYearLater = new Date($i.createdAt);
+				createdAtOneYearLater.setFullYear(createdAtOneYearLater.getFullYear() + 1);
+				if (now >= createdAtOneYearLater) {
+					claimAchievement('passedSinceAccountCreated1');
+				}
+			}
 		}
 
 		if (claimedAchievements.length >= 30) {
@@ -229,7 +241,7 @@ export async function mainBoot() {
 
 		const latestDonationInfoShownAt = miLocalStorage.getItem('latestDonationInfoShownAt');
 		const neverShowDonationInfo = miLocalStorage.getItem('neverShowDonationInfo');
-		if (neverShowDonationInfo !== 'true' && (new Date($i.createdAt).getTime() < (Date.now() - (1000 * 60 * 60 * 24 * 3))) && !location.pathname.startsWith('/miauth')) {
+		if (neverShowDonationInfo !== 'true' && (createdAt.getTime() < (Date.now() - (1000 * 60 * 60 * 24 * 3))) && !location.pathname.startsWith('/miauth')) {
 			if (latestDonationInfoShownAt == null || (new Date(latestDonationInfoShownAt).getTime() < (Date.now() - (1000 * 60 * 60 * 24 * 30)))) {
 				popup(defineAsyncComponent(() => import('@/components/MkDonation.vue')), {}, {}, 'closed');
 			}