diff --git a/conf/bleedingEdge.neon b/conf/bleedingEdge.neon
index 91201231116..306005bf3f2 100644
--- a/conf/bleedingEdge.neon
+++ b/conf/bleedingEdge.neon
@@ -32,3 +32,4 @@ parameters:
 		staticVariablesFromUsages: true
 		unusedVariable: true
 		unusedParameters: true
+		unsetOffsetOnMaybeAccessible: true
diff --git a/conf/config.neon b/conf/config.neon
index 52860b21fe9..81e074b9d7f 100644
--- a/conf/config.neon
+++ b/conf/config.neon
@@ -64,6 +64,7 @@ parameters:
 		staticVariablesFromUsages: false
 		unusedVariable: false
 		unusedParameters: false
+		unsetOffsetOnMaybeAccessible: false
 	fileExtensions:
 		- php
 	checkAdvancedIsset: false
diff --git a/conf/parametersSchema.neon b/conf/parametersSchema.neon
index 3bae9593991..758005de9dd 100644
--- a/conf/parametersSchema.neon
+++ b/conf/parametersSchema.neon
@@ -61,6 +61,7 @@ parametersSchema:
 		staticVariablesFromUsages: bool()
 		unusedVariable: bool()
 		unusedParameters: bool()
+		unsetOffsetOnMaybeAccessible: bool()
 	])
 	fileExtensions: listOf(string())
 	checkAdvancedIsset: bool()
diff --git a/src/Rules/Variables/UnsetRule.php b/src/Rules/Variables/UnsetRule.php
index d2893e17fe3..2472dd2f967 100644
--- a/src/Rules/Variables/UnsetRule.php
+++ b/src/Rules/Variables/UnsetRule.php
@@ -4,12 +4,15 @@
 
 use PhpParser\Node;
 use PHPStan\Analyser\Scope;
+use PHPStan\DependencyInjection\AutowiredParameter;
 use PHPStan\DependencyInjection\RegisteredRule;
 use PHPStan\Php\PhpVersion;
 use PHPStan\Rules\IdentifierRuleError;
 use PHPStan\Rules\Properties\PropertyReflectionFinder;
 use PHPStan\Rules\Rule;
 use PHPStan\Rules\RuleErrorBuilder;
+use PHPStan\Type\Type;
+use PHPStan\Type\TypeUtils;
 use PHPStan\Type\VerbosityLevel;
 use function is_string;
 use function sprintf;
@@ -24,6 +27,10 @@ final class UnsetRule implements Rule
 	public function __construct(
 		private PropertyReflectionFinder $propertyReflectionFinder,
 		private PhpVersion $phpVersion,
+		#[AutowiredParameter]
+		private bool $reportMaybes,
+		#[AutowiredParameter(ref: '%featureToggles.unsetOffsetOnMaybeAccessible%')]
+		private bool $unsetOffsetOnMaybeAccessible,
 	)
 	{
 	}
@@ -127,7 +134,11 @@ private function canBeUnset(Node $node, Scope $scope): ?IdentifierRuleError
 			$type = $scope->getType($node->var);
 			$dimType = $scope->getType($node->dim);
 
-			if ($type->isOffsetAccessible()->no() || $type->hasOffsetValueType($dimType)->no()) {
+			if (
+				$type->isOffsetAccessible()->no()
+				|| $type->hasOffsetValueType($dimType)->no()
+				|| $this->isOffsetMaybeNotUnsettable($type)
+			) {
 				return RuleErrorBuilder::message(
 					sprintf(
 						'Cannot unset offset %s on %s.',
@@ -146,4 +157,28 @@ private function canBeUnset(Node $node, Scope $scope): ?IdentifierRuleError
 		return null;
 	}
 
+	/**
+	 * unset() of an offset deprecates on false and throws an Error on true, an int, a float or a string,
+	 * so a union like array|false, array|int or array|string can fail at runtime.
+	 * A type whose offset access is not even legal (an object without ArrayAccess) is reported by NonexistentOffsetInArrayDimFetchRule.
+	 */
+	private function isOffsetMaybeNotUnsettable(Type $type): bool
+	{
+		if (!$this->unsetOffsetOnMaybeAccessible || !$this->reportMaybes) {
+			return false;
+		}
+
+		if (!$type->isOffsetAccessLegal()->yes()) {
+			return false;
+		}
+
+		foreach (TypeUtils::flattenTypes($type) as $innerType) {
+			if ($innerType->isScalar()->yes()) {
+				return true;
+			}
+		}
+
+		return false;
+	}
+
 }
diff --git a/tests/PHPStan/Rules/Variables/UnsetRuleTest.php b/tests/PHPStan/Rules/Variables/UnsetRuleTest.php
index 73515e60d5f..a43b03aee3b 100644
--- a/tests/PHPStan/Rules/Variables/UnsetRuleTest.php
+++ b/tests/PHPStan/Rules/Variables/UnsetRuleTest.php
@@ -16,12 +16,18 @@
 class UnsetRuleTest extends RuleTestCase
 {
 
+	private bool $reportMaybes = false;
+
+	private bool $unsetOffsetOnMaybeAccessible = false;
+
 	protected function getRule(): Rule
 	{
 		$container = self::getContainer();
 		return new UnsetRule(
 			$container->getByType(PropertyReflectionFinder::class),
 			$container->getByType(PhpVersion::class),
+			$this->reportMaybes,
+			$this->unsetOffsetOnMaybeAccessible,
 		);
 	}
 
@@ -229,4 +235,64 @@ public function testNullCoalesceAssignRightSideScope(): void
 		$this->analyse([__DIR__ . '/data/null-coalesce-assign-right-side-scope.php'], []);
 	}
 
+	public function testUnsetOffsetOnMaybeAccessible(): void
+	{
+		$this->reportMaybes = true;
+		$this->unsetOffsetOnMaybeAccessible = true;
+		$this->analyse([__DIR__ . '/data/unset-offset-maybe-accessible.php'], [
+			[
+				'Cannot unset offset \'port\' on array{port?: int, path?: string}|false.',
+				13,
+			],
+			[
+				'Cannot unset offset \'port\' on array<string, int>|int.',
+				21,
+			],
+			[
+				'Cannot unset offset \'port\' on array{scheme?: string, host?: string, port?: int<0, 65535>, user?: string, pass?: string, path?: string, query?: string, fragment?: string}|false.',
+				56,
+			],
+			[
+				'Cannot unset offset \'port\' on array<string, int>|bool.',
+				91,
+			],
+			[
+				'Cannot unset offset \'port\' on array<string, int>|true.',
+				92,
+			],
+			[
+				'Cannot unset offset \'port\' on array<string, int>|float.',
+				93,
+			],
+			[
+				'Cannot unset offset \'port\' on array<string, int>|false.',
+				101,
+			],
+		]);
+	}
+
+	public function testUnsetOffsetOnMaybeAccessibleWithoutReportMaybes(): void
+	{
+		$this->unsetOffsetOnMaybeAccessible = true;
+		$this->analyse([__DIR__ . '/data/unset-offset-maybe-accessible.php'], []);
+	}
+
+	public function testUnsetOffsetOnMaybeAccessibleWithoutFeatureToggle(): void
+	{
+		$this->reportMaybes = true;
+		$this->analyse([__DIR__ . '/data/unset-offset-maybe-accessible.php'], []);
+	}
+
+	public function testUnsetOffsetOnMaybeAccessibleTemplate(): void
+	{
+		$this->reportMaybes = true;
+		$this->unsetOffsetOnMaybeAccessible = true;
+		$this->analyse([__DIR__ . '/data/unset-offset-maybe-accessible-template.php'], [
+			[
+				'Cannot unset offset \'port\' on array<string, int>|(T of array<string, int>|false).',
+				11,
+			],
+		]);
+	}
+
 }
diff --git a/tests/PHPStan/Rules/Variables/data/unset-offset-maybe-accessible-template.php b/tests/PHPStan/Rules/Variables/data/unset-offset-maybe-accessible-template.php
new file mode 100644
index 00000000000..eef0d2a1e05
--- /dev/null
+++ b/tests/PHPStan/Rules/Variables/data/unset-offset-maybe-accessible-template.php
@@ -0,0 +1,12 @@
+<?php
+
+namespace UnsetOffsetMaybeAccessibleTemplate;
+
+/**
+ * @template T of array<string, int>|false
+ * @param array<string, int>|T $value
+ */
+function foo($value): void
+{
+	unset($value['port']);
+}
diff --git a/tests/PHPStan/Rules/Variables/data/unset-offset-maybe-accessible.php b/tests/PHPStan/Rules/Variables/data/unset-offset-maybe-accessible.php
new file mode 100644
index 00000000000..f6020cfd9c1
--- /dev/null
+++ b/tests/PHPStan/Rules/Variables/data/unset-offset-maybe-accessible.php
@@ -0,0 +1,120 @@
+<?php // lint >= 8.0
+
+namespace UnsetOffsetMaybeAccessible;
+
+class Foo
+{
+
+	/**
+	 * @param array{port?: int, path?: string}|false $parsed
+	 */
+	public function arrayOrFalse($parsed): void
+	{
+		unset($parsed['port']);
+	}
+
+	/**
+	 * @param array<string, int>|int $value
+	 */
+	public function arrayOrInt($value): void
+	{
+		unset($value['port']);
+	}
+
+	/**
+	 * @param array<string, int>|null $value
+	 */
+	public function arrayOrNull($value): void
+	{
+		unset($value['port']);
+	}
+
+	/**
+	 * @param array<string, int>|\ArrayAccess<string, int> $value
+	 */
+	public function arrayOrArrayAccess($value): void
+	{
+		unset($value['port']);
+	}
+
+	/**
+	 * @param array<string, int> $value
+	 */
+	public function array($value): void
+	{
+		unset($value['port']);
+	}
+
+	public function object(\stdClass $value): void
+	{
+		unset($value['port']);
+	}
+
+	public function parseUrl(string $url): void
+	{
+		$parsed = parse_url($url);
+		unset($parsed['port']);
+	}
+
+	public function explicitMixed(mixed $value): void
+	{
+		unset($value['port']);
+	}
+
+	public function implicitMixed($value): void
+	{
+		unset($value['port']);
+	}
+
+	public function mixedWithoutFalse(mixed $value): void
+	{
+		if ($value !== false) {
+			unset($value['port']);
+		}
+	}
+
+	public function jsonDecodedAfterIsset(string $json): void
+	{
+		$body = json_decode($json, true);
+		if (isset($body['ttl'])) {
+			unset($body['ttl']);
+		}
+	}
+
+	/**
+	 * @param array<string, int>|bool $bool
+	 * @param array<string, int>|true $true
+	 * @param array<string, int>|float $float
+	 */
+	public function scalars($bool, $true, $float): void
+	{
+		unset($bool['port']);
+		unset($true['port']);
+		unset($float['port']);
+	}
+
+	/**
+	 * @param array{x: array<string, int>|false} $value
+	 */
+	public function nested(array $value): void
+	{
+		unset($value['x']['port']);
+	}
+
+	/**
+	 * @param array<string, int>|\stdClass $value
+	 */
+	public function arrayOrObject($value): void
+	{
+		unset($value['port']);
+	}
+
+	/**
+	 * @param \stdClass|int $value
+	 */
+	public function objectOrInt($value): void
+	{
+		unset($value['port']);
+	}
+
+}