diff --git a/src/Analyser/MutatingScope.php b/src/Analyser/MutatingScope.php
index 6e785c8d45..fddb980225 100644
--- a/src/Analyser/MutatingScope.php
+++ b/src/Analyser/MutatingScope.php
@@ -50,6 +50,7 @@
 use PHPStan\TrinaryLogic;
 use PHPStan\Type\Accessory\AccessoryLiteralStringType;
 use PHPStan\Type\Accessory\AccessoryNonEmptyStringType;
+use PHPStan\Type\Accessory\NonEmptyArrayType;
 use PHPStan\Type\ArrayType;
 use PHPStan\Type\BenevolentUnionType;
 use PHPStan\Type\BooleanType;
@@ -1290,6 +1291,7 @@ private function resolveType(Expr $node): Type
 
 					return TypeCombinator::union(...$resultTypes);
 				}
+
 				$arrayType = new ArrayType(new MixedType(), new MixedType());
 
 				if ($arrayType->isSuperTypeOf($leftType)->yes() && $arrayType->isSuperTypeOf($rightType)->yes()) {
@@ -1306,10 +1308,16 @@ private function resolveType(Expr $node): Type
 						}
 						$keyType = TypeCombinator::union(...$keyTypes);
 					}
-					return new ArrayType(
+
+					$arrayType = new ArrayType(
 						$keyType,
 						TypeCombinator::union($leftType->getIterableValueType(), $rightType->getIterableValueType())
 					);
+
+					if ($leftType->isIterableAtLeastOnce()->yes() || $rightType->isIterableAtLeastOnce()->yes()) {
+						return TypeCombinator::intersect($arrayType, new NonEmptyArrayType());
+					}
+					return $arrayType;
 				}
 
 				if ($leftType instanceof MixedType && $rightType instanceof MixedType) {
diff --git a/tests/PHPStan/Analyser/LegacyNodeScopeResolverTest.php b/tests/PHPStan/Analyser/LegacyNodeScopeResolverTest.php
index 6cdf52184c..d224a419e5 100644
--- a/tests/PHPStan/Analyser/LegacyNodeScopeResolverTest.php
+++ b/tests/PHPStan/Analyser/LegacyNodeScopeResolverTest.php
@@ -2830,7 +2830,7 @@ public function dataBinaryOperations(): array
 				'[1, 2, 3] + [4, 5, 6]',
 			],
 			[
-				'array<int>',
+				'non-empty-array<int>',
 				'$arrayOfUnknownIntegers + [1, 2, 3]',
 			],
 			[
diff --git a/tests/PHPStan/Analyser/NodeScopeResolverTest.php b/tests/PHPStan/Analyser/NodeScopeResolverTest.php
index e09cc3a426..ffca869fb5 100644
--- a/tests/PHPStan/Analyser/NodeScopeResolverTest.php
+++ b/tests/PHPStan/Analyser/NodeScopeResolverTest.php
@@ -272,6 +272,7 @@ public function dataFileAsserts(): iterable
 		yield from $this->gatherAssertTypes(__DIR__ . '/data/array-map.php');
 		yield from $this->gatherAssertTypes(__DIR__ . '/data/array-map-closure.php');
 		yield from $this->gatherAssertTypes(__DIR__ . '/data/array-sum.php');
+		yield from $this->gatherAssertTypes(__DIR__ . '/data/array-plus.php');
 		yield from $this->gatherAssertTypes(__DIR__ . '/data/bug-4573.php');
 		yield from $this->gatherAssertTypes(__DIR__ . '/data/bug-4577.php');
 		yield from $this->gatherAssertTypes(__DIR__ . '/data/bug-4579.php');
diff --git a/tests/PHPStan/Analyser/data/array-plus.php b/tests/PHPStan/Analyser/data/array-plus.php
new file mode 100644
index 0000000000..b6d8b99e2d
--- /dev/null
+++ b/tests/PHPStan/Analyser/data/array-plus.php
@@ -0,0 +1,20 @@
+<?php
+
+namespace ArrayPlus;
+
+use function PHPStan\Testing\assertType;
+
+class Foo
+{
+	/**
+	 * @param non-empty-array $s2
+	 */
+	public function doFoo(array $s1, $s2)
+	{
+		assertType('non-empty-array', $s1 + $s2);
+		assertType('non-empty-array', $s2 + $s1);
+		assertType('non-empty-array', $s2 + $s2);
+
+		assertType('array', $s1 + $s1);
+	}
+}