diff --git a/.changeset/rich-dogs-design.md b/.changeset/rich-dogs-design.md
new file mode 100644
index 000000000..0ef7fbf2c
--- /dev/null
+++ b/.changeset/rich-dogs-design.md
@@ -0,0 +1,5 @@
+---
+'eslint-plugin-svelte': minor
+---
+
+feat: added the `require-event-prefix` rule
diff --git a/README.md b/README.md
index 351738e05..136757414 100644
--- a/README.md
+++ b/README.md
@@ -335,6 +335,7 @@ These rules relate to style guidelines, and are therefore quite subjective:
 | [svelte/no-spaces-around-equal-signs-in-attribute](https://sveltejs.github.io/eslint-plugin-svelte/rules/no-spaces-around-equal-signs-in-attribute/) | disallow spaces around equal signs in attribute | :wrench: |
 | [svelte/prefer-class-directive](https://sveltejs.github.io/eslint-plugin-svelte/rules/prefer-class-directive/) | require class directives instead of ternary expressions | :wrench: |
 | [svelte/prefer-style-directive](https://sveltejs.github.io/eslint-plugin-svelte/rules/prefer-style-directive/) | require style directives instead of style attribute | :wrench: |
+| [svelte/require-event-prefix](https://sveltejs.github.io/eslint-plugin-svelte/rules/require-event-prefix/) | require component event names to start with "on" |  |
 | [svelte/shorthand-attribute](https://sveltejs.github.io/eslint-plugin-svelte/rules/shorthand-attribute/) | enforce use of shorthand syntax in attribute | :wrench: |
 | [svelte/shorthand-directive](https://sveltejs.github.io/eslint-plugin-svelte/rules/shorthand-directive/) | enforce use of shorthand syntax in directives | :wrench: |
 | [svelte/sort-attributes](https://sveltejs.github.io/eslint-plugin-svelte/rules/sort-attributes/) | enforce order of attributes | :wrench: |
diff --git a/docs/rules.md b/docs/rules.md
index 7d2834a7c..1fd78e202 100644
--- a/docs/rules.md
+++ b/docs/rules.md
@@ -92,6 +92,7 @@ These rules relate to style guidelines, and are therefore quite subjective:
 | [svelte/no-spaces-around-equal-signs-in-attribute](./rules/no-spaces-around-equal-signs-in-attribute.md) | disallow spaces around equal signs in attribute                                    | :wrench: |
 | [svelte/prefer-class-directive](./rules/prefer-class-directive.md)                                       | require class directives instead of ternary expressions                            | :wrench: |
 | [svelte/prefer-style-directive](./rules/prefer-style-directive.md)                                       | require style directives instead of style attribute                                | :wrench: |
+| [svelte/require-event-prefix](./rules/require-event-prefix.md)                                           | require component event names to start with "on"                                   |          |
 | [svelte/shorthand-attribute](./rules/shorthand-attribute.md)                                             | enforce use of shorthand syntax in attribute                                       | :wrench: |
 | [svelte/shorthand-directive](./rules/shorthand-directive.md)                                             | enforce use of shorthand syntax in directives                                      | :wrench: |
 | [svelte/sort-attributes](./rules/sort-attributes.md)                                                     | enforce order of attributes                                                        | :wrench: |
diff --git a/docs/rules/require-event-prefix.md b/docs/rules/require-event-prefix.md
new file mode 100644
index 000000000..556509c6e
--- /dev/null
+++ b/docs/rules/require-event-prefix.md
@@ -0,0 +1,71 @@
+---
+pageClass: 'rule-details'
+sidebarDepth: 0
+title: 'svelte/require-event-prefix'
+description: 'require component event names to start with "on"'
+---
+
+# svelte/require-event-prefix
+
+> require component event names to start with "on"
+
+- :exclamation: <badge text="This rule has not been released yet." vertical="middle" type="error"> **_This rule has not been released yet._** </badge>
+
+## :book: Rule Details
+
+Starting with Svelte 5, component events are just component props that are functions and so can be called like any function. Events for HTML elements all have their name begin with "on" (e.g. `onclick`). This rule enforces that all component events (i.e. function props) also begin with "on".
+
+<!--eslint-skip-->
+
+```svelte
+<script lang="ts">
+  /* eslint svelte/require-event-prefix: "error" */
+
+  /* ✓ GOOD */
+
+  interface Props {
+    regularProp: string;
+    onclick(): void;
+  }
+
+  let { regularProp, onclick }: Props = $props();
+</script>
+```
+
+```svelte
+<script lang="ts">
+  /* eslint svelte/require-event-prefix: "error" */
+
+  /* ✗ BAD */
+
+  interface Props {
+    click(): void;
+  }
+
+  let { click }: Props = $props();
+</script>
+```
+
+## :wrench: Options
+
+```json
+{
+  "svelte/require-event-prefix": [
+    "error",
+    {
+      "checkAsyncFunctions": false
+    }
+  ]
+}
+```
+
+- `checkAsyncFunctions` ... Whether to also report asychronous function properties. Default `false`.
+
+## :books: Further Reading
+
+- [Svelte docs on events in version 5](https://svelte.dev/docs/svelte/v5-migration-guide#Event-changes)
+
+## :mag: Implementation
+
+- [Rule source](https://github.com/sveltejs/eslint-plugin-svelte/blob/main/packages/eslint-plugin-svelte/src/rules/require-event-prefix.ts)
+- [Test source](https://github.com/sveltejs/eslint-plugin-svelte/blob/main/packages/eslint-plugin-svelte/tests/src/rules/require-event-prefix.ts)
diff --git a/packages/eslint-plugin-svelte/src/rule-types.ts b/packages/eslint-plugin-svelte/src/rule-types.ts
index 88c07aca1..32c01e6d4 100644
--- a/packages/eslint-plugin-svelte/src/rule-types.ts
+++ b/packages/eslint-plugin-svelte/src/rule-types.ts
@@ -306,6 +306,11 @@ export interface RuleOptions {
    * @see https://sveltejs.github.io/eslint-plugin-svelte/rules/require-event-dispatcher-types/
    */
   'svelte/require-event-dispatcher-types'?: Linter.RuleEntry<[]>
+  /**
+   * require component event names to start with "on"
+   * @see https://sveltejs.github.io/eslint-plugin-svelte/rules/require-event-prefix/
+   */
+  'svelte/require-event-prefix'?: Linter.RuleEntry<SvelteRequireEventPrefix>
   /**
    * require style attributes that can be optimized
    * @see https://sveltejs.github.io/eslint-plugin-svelte/rules/require-optimized-style-attribute/
@@ -532,6 +537,10 @@ type SveltePreferConst = []|[{
   ignoreReadBeforeAssign?: boolean
   excludedRunes?: string[]
 }]
+// ----- svelte/require-event-prefix -----
+type SvelteRequireEventPrefix = []|[{
+  checkAsyncFunctions?: boolean
+}]
 // ----- svelte/shorthand-attribute -----
 type SvelteShorthandAttribute = []|[{
   prefer?: ("always" | "never")
diff --git a/packages/eslint-plugin-svelte/src/rules/require-event-prefix.ts b/packages/eslint-plugin-svelte/src/rules/require-event-prefix.ts
new file mode 100644
index 000000000..65870e3ae
--- /dev/null
+++ b/packages/eslint-plugin-svelte/src/rules/require-event-prefix.ts
@@ -0,0 +1,122 @@
+import { createRule } from '../utils/index.js';
+import { type TSTools, getTypeScriptTools } from '../utils/ts-utils/index.js';
+import {
+	type MethodSignature,
+	type Symbol,
+	SymbolFlags,
+	SyntaxKind,
+	type Type,
+	type TypeReferenceNode,
+	type PropertySignature
+} from 'typescript';
+import type { CallExpression } from 'estree';
+
+export default createRule('require-event-prefix', {
+	meta: {
+		docs: {
+			description: 'require component event names to start with "on"',
+			category: 'Stylistic Issues',
+			conflictWithPrettier: false,
+			recommended: false
+		},
+		schema: [
+			{
+				type: 'object',
+				properties: {
+					checkAsyncFunctions: {
+						type: 'boolean'
+					}
+				},
+				additionalProperties: false
+			}
+		],
+		messages: {
+			nonPrefixedFunction: 'Component event name must start with "on".'
+		},
+		type: 'suggestion',
+		conditions: [
+			{
+				svelteVersions: ['5'],
+				svelteFileTypes: ['.svelte']
+			}
+		]
+	},
+	create(context) {
+		const tsTools = getTypeScriptTools(context);
+		if (!tsTools) {
+			return {};
+		}
+
+		const checkAsyncFunctions = context.options[0]?.checkAsyncFunctions ?? false;
+
+		return {
+			CallExpression(node) {
+				const propsType = getPropsType(node, tsTools);
+				if (propsType === undefined) {
+					return;
+				}
+				for (const property of propsType.getProperties()) {
+					if (
+						isFunctionLike(property) &&
+						!property.getName().startsWith('on') &&
+						(checkAsyncFunctions || !isFunctionAsync(property))
+					) {
+						const declarationTsNode = property.getDeclarations()?.[0];
+						const declarationEstreeNode =
+							declarationTsNode !== undefined
+								? tsTools.service.tsNodeToESTreeNodeMap.get(declarationTsNode)
+								: undefined;
+						context.report({
+							node: declarationEstreeNode ?? node,
+							messageId: 'nonPrefixedFunction'
+						});
+					}
+				}
+			}
+		};
+	}
+});
+
+function getPropsType(node: CallExpression, tsTools: TSTools): Type | undefined {
+	if (
+		node.callee.type !== 'Identifier' ||
+		node.callee.name !== '$props' ||
+		node.parent.type !== 'VariableDeclarator'
+	) {
+		return undefined;
+	}
+
+	const tsNode = tsTools.service.esTreeNodeToTSNodeMap.get(node.parent.id);
+	if (tsNode === undefined) {
+		return undefined;
+	}
+
+	return tsTools.service.program.getTypeChecker().getTypeAtLocation(tsNode);
+}
+
+function isFunctionLike(functionSymbol: Symbol): boolean {
+	return (
+		(functionSymbol.getFlags() & SymbolFlags.Method) !== 0 ||
+		(functionSymbol.valueDeclaration?.kind === SyntaxKind.PropertySignature &&
+			(functionSymbol.valueDeclaration as PropertySignature).type?.kind === SyntaxKind.FunctionType)
+	);
+}
+
+function isFunctionAsync(functionSymbol: Symbol): boolean {
+	return (
+		functionSymbol.getDeclarations()?.some((declaration) => {
+			if (declaration.kind !== SyntaxKind.MethodSignature) {
+				return false;
+			}
+			const declarationType = (declaration as MethodSignature).type;
+			if (declarationType?.kind !== SyntaxKind.TypeReference) {
+				return false;
+			}
+			const declarationTypeName = (declarationType as TypeReferenceNode).typeName;
+			return (
+				declarationTypeName.kind === SyntaxKind.Identifier &&
+				declarationTypeName.escapedText === 'Promise'
+			);
+		}) ?? false
+	);
+}
diff --git a/packages/eslint-plugin-svelte/src/utils/rules.ts b/packages/eslint-plugin-svelte/src/utils/rules.ts
index 13d3bd65c..176be5a6b 100644
--- a/packages/eslint-plugin-svelte/src/utils/rules.ts
+++ b/packages/eslint-plugin-svelte/src/utils/rules.ts
@@ -60,6 +60,7 @@ import preferDestructuredStoreProps from '../rules/prefer-destructured-store-pro
 import preferStyleDirective from '../rules/prefer-style-directive.js';
 import requireEachKey from '../rules/require-each-key.js';
 import requireEventDispatcherTypes from '../rules/require-event-dispatcher-types.js';
+import requireEventPrefix from '../rules/require-event-prefix.js';
 import requireOptimizedStyleAttribute from '../rules/require-optimized-style-attribute.js';
 import requireStoreCallbacksUseSetParam from '../rules/require-store-callbacks-use-set-param.js';
 import requireStoreReactiveAccess from '../rules/require-store-reactive-access.js';
@@ -133,6 +134,7 @@ export const rules = [
 	preferStyleDirective,
 	requireEachKey,
 	requireEventDispatcherTypes,
+	requireEventPrefix,
 	requireOptimizedStyleAttribute,
 	requireStoreCallbacksUseSetParam,
 	requireStoreReactiveAccess,
diff --git a/packages/eslint-plugin-svelte/tests/fixtures/rules/require-event-prefix/invalid/_requirements.json b/packages/eslint-plugin-svelte/tests/fixtures/rules/require-event-prefix/invalid/_requirements.json
new file mode 100644
index 000000000..498661308
--- /dev/null
+++ b/packages/eslint-plugin-svelte/tests/fixtures/rules/require-event-prefix/invalid/_requirements.json
@@ -0,0 +1,3 @@
+{
+	"svelte": ">=5.0.0"
+}
diff --git a/packages/eslint-plugin-svelte/tests/fixtures/rules/require-event-prefix/invalid/checkAsyncFunctions/_config.json b/packages/eslint-plugin-svelte/tests/fixtures/rules/require-event-prefix/invalid/checkAsyncFunctions/_config.json
new file mode 100644
index 000000000..a0f52ed6e
--- /dev/null
+++ b/packages/eslint-plugin-svelte/tests/fixtures/rules/require-event-prefix/invalid/checkAsyncFunctions/_config.json
@@ -0,0 +1,3 @@
+{
+	"options": [{ "checkAsyncFunctions": true }]
+}
diff --git a/packages/eslint-plugin-svelte/tests/fixtures/rules/require-event-prefix/invalid/checkAsyncFunctions/_requirements.json b/packages/eslint-plugin-svelte/tests/fixtures/rules/require-event-prefix/invalid/checkAsyncFunctions/_requirements.json
new file mode 100644
index 000000000..498661308
--- /dev/null
+++ b/packages/eslint-plugin-svelte/tests/fixtures/rules/require-event-prefix/invalid/checkAsyncFunctions/_requirements.json
@@ -0,0 +1,3 @@
+{
+	"svelte": ">=5.0.0"
+}
diff --git a/packages/eslint-plugin-svelte/tests/fixtures/rules/require-event-prefix/invalid/checkAsyncFunctions/async-arrow01-errors.yaml b/packages/eslint-plugin-svelte/tests/fixtures/rules/require-event-prefix/invalid/checkAsyncFunctions/async-arrow01-errors.yaml
new file mode 100644
index 000000000..4c26d4e62
--- /dev/null
+++ b/packages/eslint-plugin-svelte/tests/fixtures/rules/require-event-prefix/invalid/checkAsyncFunctions/async-arrow01-errors.yaml
@@ -0,0 +1,4 @@
+- message: Component event name must start with "on".
+  line: 3
+  column: 5
+  suggestions: null
diff --git a/packages/eslint-plugin-svelte/tests/fixtures/rules/require-event-prefix/invalid/checkAsyncFunctions/async-arrow01-input.svelte b/packages/eslint-plugin-svelte/tests/fixtures/rules/require-event-prefix/invalid/checkAsyncFunctions/async-arrow01-input.svelte
new file mode 100644
index 000000000..0b0502984
--- /dev/null
+++ b/packages/eslint-plugin-svelte/tests/fixtures/rules/require-event-prefix/invalid/checkAsyncFunctions/async-arrow01-input.svelte
@@ -0,0 +1,9 @@
+<script lang="ts">
+  interface Props {
+    custom: () => Promise<void>;
+  }
+
+  let { custom }: Props = $props();
+
+  void custom();
+</script>
diff --git a/packages/eslint-plugin-svelte/tests/fixtures/rules/require-event-prefix/invalid/checkAsyncFunctions/async01-errors.yaml b/packages/eslint-plugin-svelte/tests/fixtures/rules/require-event-prefix/invalid/checkAsyncFunctions/async01-errors.yaml
new file mode 100644
index 000000000..4c26d4e62
--- /dev/null
+++ b/packages/eslint-plugin-svelte/tests/fixtures/rules/require-event-prefix/invalid/checkAsyncFunctions/async01-errors.yaml
@@ -0,0 +1,4 @@
+- message: Component event name must start with "on".
+  line: 3
+  column: 5
+  suggestions: null
diff --git a/packages/eslint-plugin-svelte/tests/fixtures/rules/require-event-prefix/invalid/checkAsyncFunctions/async01-input.svelte b/packages/eslint-plugin-svelte/tests/fixtures/rules/require-event-prefix/invalid/checkAsyncFunctions/async01-input.svelte
new file mode 100644
index 000000000..4f6f3ee49
--- /dev/null
+++ b/packages/eslint-plugin-svelte/tests/fixtures/rules/require-event-prefix/invalid/checkAsyncFunctions/async01-input.svelte
@@ -0,0 +1,9 @@
+<script lang="ts">
+  interface Props {
+    custom(): Promise<void>;
+  }
+
+  let { custom }: Props = $props();
+
+  void custom();
+</script>
diff --git a/packages/eslint-plugin-svelte/tests/fixtures/rules/require-event-prefix/invalid/no-prefix-arrow01-errors.yaml b/packages/eslint-plugin-svelte/tests/fixtures/rules/require-event-prefix/invalid/no-prefix-arrow01-errors.yaml
new file mode 100644
index 000000000..4c26d4e62
--- /dev/null
+++ b/packages/eslint-plugin-svelte/tests/fixtures/rules/require-event-prefix/invalid/no-prefix-arrow01-errors.yaml
@@ -0,0 +1,4 @@
+- message: Component event name must start with "on".
+  line: 3
+  column: 5
+  suggestions: null
diff --git a/packages/eslint-plugin-svelte/tests/fixtures/rules/require-event-prefix/invalid/no-prefix-arrow01-input.svelte b/packages/eslint-plugin-svelte/tests/fixtures/rules/require-event-prefix/invalid/no-prefix-arrow01-input.svelte
new file mode 100644
index 000000000..7874e51da
--- /dev/null
+++ b/packages/eslint-plugin-svelte/tests/fixtures/rules/require-event-prefix/invalid/no-prefix-arrow01-input.svelte
@@ -0,0 +1,9 @@
+<script lang="ts">
+  interface Props {
+    custom: () => void;
+  }
+
+  let { custom }: Props = $props();
+
+  custom();
+</script>
diff --git a/packages/eslint-plugin-svelte/tests/fixtures/rules/require-event-prefix/invalid/no-prefix-inline-type01-errors.yaml b/packages/eslint-plugin-svelte/tests/fixtures/rules/require-event-prefix/invalid/no-prefix-inline-type01-errors.yaml
new file mode 100644
index 000000000..affa6e169
--- /dev/null
+++ b/packages/eslint-plugin-svelte/tests/fixtures/rules/require-event-prefix/invalid/no-prefix-inline-type01-errors.yaml
@@ -0,0 +1,4 @@
+- message: Component event name must start with "on".
+  line: 2
+  column: 21
+  suggestions: null
diff --git a/packages/eslint-plugin-svelte/tests/fixtures/rules/require-event-prefix/invalid/no-prefix-inline-type01-input.svelte b/packages/eslint-plugin-svelte/tests/fixtures/rules/require-event-prefix/invalid/no-prefix-inline-type01-input.svelte
new file mode 100644
index 000000000..3fc3c616b
--- /dev/null
+++ b/packages/eslint-plugin-svelte/tests/fixtures/rules/require-event-prefix/invalid/no-prefix-inline-type01-input.svelte
@@ -0,0 +1,5 @@
+<script lang="ts">
+  let { custom }: { custom(): void } = $props();
+
+  custom();
+</script>
diff --git a/packages/eslint-plugin-svelte/tests/fixtures/rules/require-event-prefix/invalid/no-prefix01-errors.yaml b/packages/eslint-plugin-svelte/tests/fixtures/rules/require-event-prefix/invalid/no-prefix01-errors.yaml
new file mode 100644
index 000000000..4c26d4e62
--- /dev/null
+++ b/packages/eslint-plugin-svelte/tests/fixtures/rules/require-event-prefix/invalid/no-prefix01-errors.yaml
@@ -0,0 +1,4 @@
+- message: Component event name must start with "on".
+  line: 3
+  column: 5
+  suggestions: null
diff --git a/packages/eslint-plugin-svelte/tests/fixtures/rules/require-event-prefix/invalid/no-prefix01-input.svelte b/packages/eslint-plugin-svelte/tests/fixtures/rules/require-event-prefix/invalid/no-prefix01-input.svelte
new file mode 100644
index 000000000..036a1d65b
--- /dev/null
+++ b/packages/eslint-plugin-svelte/tests/fixtures/rules/require-event-prefix/invalid/no-prefix01-input.svelte
@@ -0,0 +1,9 @@
+<script lang="ts">
+  interface Props {
+    custom(): void;
+  }
+
+  let { custom }: Props = $props();
+
+  custom();
+</script>
diff --git a/packages/eslint-plugin-svelte/tests/fixtures/rules/require-event-prefix/valid/_requirements.json b/packages/eslint-plugin-svelte/tests/fixtures/rules/require-event-prefix/valid/_requirements.json
new file mode 100644
index 000000000..498661308
--- /dev/null
+++ b/packages/eslint-plugin-svelte/tests/fixtures/rules/require-event-prefix/valid/_requirements.json
@@ -0,0 +1,3 @@
+{
+	"svelte": ">=5.0.0"
+}
diff --git a/packages/eslint-plugin-svelte/tests/fixtures/rules/require-event-prefix/valid/any01-input.svelte b/packages/eslint-plugin-svelte/tests/fixtures/rules/require-event-prefix/valid/any01-input.svelte
new file mode 100644
index 000000000..deeb82509
--- /dev/null
+++ b/packages/eslint-plugin-svelte/tests/fixtures/rules/require-event-prefix/valid/any01-input.svelte
@@ -0,0 +1,9 @@
+<script lang="ts">
+  interface Props {
+    custom: any;
+  }
+
+  let { custom }: Props = $props();
+
+  console.log(custom);
+</script>
diff --git a/packages/eslint-plugin-svelte/tests/fixtures/rules/require-event-prefix/valid/async01-input.svelte b/packages/eslint-plugin-svelte/tests/fixtures/rules/require-event-prefix/valid/async01-input.svelte
new file mode 100644
index 000000000..4f6f3ee49
--- /dev/null
+++ b/packages/eslint-plugin-svelte/tests/fixtures/rules/require-event-prefix/valid/async01-input.svelte
@@ -0,0 +1,9 @@
+<script lang="ts">
+  interface Props {
+    custom(): Promise<void>;
+  }
+
+  let { custom }: Props = $props();
+
+  void custom();
+</script>
diff --git a/packages/eslint-plugin-svelte/tests/fixtures/rules/require-event-prefix/valid/non-function01-input.svelte b/packages/eslint-plugin-svelte/tests/fixtures/rules/require-event-prefix/valid/non-function01-input.svelte
new file mode 100644
index 000000000..d23e387a1
--- /dev/null
+++ b/packages/eslint-plugin-svelte/tests/fixtures/rules/require-event-prefix/valid/non-function01-input.svelte
@@ -0,0 +1,9 @@
+<script lang="ts">
+  interface Props {
+    custom: number;
+  }
+
+  let { custom }: Props = $props();
+
+  console.log(custom);
+</script>
diff --git a/packages/eslint-plugin-svelte/tests/fixtures/rules/require-event-prefix/valid/with-prefix01-input.svelte b/packages/eslint-plugin-svelte/tests/fixtures/rules/require-event-prefix/valid/with-prefix01-input.svelte
new file mode 100644
index 000000000..e3396af33
--- /dev/null
+++ b/packages/eslint-plugin-svelte/tests/fixtures/rules/require-event-prefix/valid/with-prefix01-input.svelte
@@ -0,0 +1,9 @@
+<script lang="ts">
+  interface Props {
+    oncustom(): void;
+  }
+
+  let { oncustom }: Props = $props();
+
+  oncustom();
+</script>
diff --git a/packages/eslint-plugin-svelte/tests/src/rules/require-event-prefix.ts b/packages/eslint-plugin-svelte/tests/src/rules/require-event-prefix.ts
new file mode 100644
index 000000000..7818735b5
--- /dev/null
+++ b/packages/eslint-plugin-svelte/tests/src/rules/require-event-prefix.ts
@@ -0,0 +1,12 @@
+import { RuleTester } from '../../utils/eslint-compat.js';
+import rule from '../../../src/rules/require-event-prefix.js';
+import { loadTestCases } from '../../utils/utils.js';
+
+const tester = new RuleTester({
+	languageOptions: {
+		ecmaVersion: 2020,
+		sourceType: 'module'
+	}
+});
+
+tester.run('require-event-prefix', rule as any, loadTestCases('require-event-prefix'));