diff --git a/.github/workflows/continuous-integration.yaml b/.github/workflows/continuous-integration.yaml
index 577b726307..cbd6cc3879 100644
--- a/.github/workflows/continuous-integration.yaml
+++ b/.github/workflows/continuous-integration.yaml
@@ -14,7 +14,7 @@ jobs:
           php-version: '7.0'
           coverage: 'none'
           extensions: 'json, mbstring, tokenizer'
-          tools: 'php-cs-fixer:2.14.0'
+          tools: 'php-cs-fixer:2.19.3'
 
       - name: 'Check PHP code'
         run: |
@@ -39,6 +39,8 @@ jobs:
             elasticsearch: '6.5.2'
           - php: '8.0'
             elasticsearch: '6.5.2'
+          - php: '8.1'
+            elasticsearch: '6.5.2'
       fail-fast: false
     steps:
       - name: 'Checkout'
diff --git a/.php_cs.dist b/.php_cs.dist
index 19ff470165..72b69fb6ef 100644
--- a/.php_cs.dist
+++ b/.php_cs.dist
@@ -18,6 +18,7 @@ $config = PhpCsFixer\Config::create()
         'no_useless_else' => true,
         '@PHPUnit60Migration:risky' => true,
         'php_unit_dedicate_assert' => ['target' => 'newest'],
+        'no_superfluous_phpdoc_tags' => false,
     ])
 ;
 
diff --git a/CHANGELOG.md b/CHANGELOG.md
index d83f274fb8..b72aeeab5e 100755
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -7,6 +7,7 @@ All notable changes to this project will be documented in this file based on the
 ### Bugfixes
 ### Added
 ### Improvements
+* Solve PHP 8.1 deprecations for every class implementing Countable, Iterator or ArrayAccess [#2061](https://github.com/ruflin/Elastica/pull/2061)
 ### Deprecated
 
 ## [6.2.0](https://github.com/ruflin/Elastica/compare/6.1.5...6.2.0)
diff --git a/lib/Elastica/Aggregation/AbstractSimpleAggregation.php b/lib/Elastica/Aggregation/AbstractSimpleAggregation.php
index 88210a0953..ba81bacbf6 100644
--- a/lib/Elastica/Aggregation/AbstractSimpleAggregation.php
+++ b/lib/Elastica/Aggregation/AbstractSimpleAggregation.php
@@ -36,9 +36,7 @@ public function setScript($script)
     public function toArray()
     {
         if (!$this->hasParam('field') && !$this->hasParam('script')) {
-            throw new InvalidException(
-                'Either the field param or the script param should be set'
-            );
+            throw new InvalidException('Either the field param or the script param should be set');
         }
         $array = parent::toArray();
 
diff --git a/lib/Elastica/ArrayableInterface.php b/lib/Elastica/ArrayableInterface.php
index 1f92e8a41a..5e6b4debf3 100644
--- a/lib/Elastica/ArrayableInterface.php
+++ b/lib/Elastica/ArrayableInterface.php
@@ -5,7 +5,6 @@
 /**
  * Interface for params.
  *
- *
  * @author Evgeniy Sokolov <ewgraf@gmail.com>
  */
 interface ArrayableInterface
diff --git a/lib/Elastica/Bulk/ResponseSet.php b/lib/Elastica/Bulk/ResponseSet.php
index 0bcb5e9d90..adf754c4d4 100644
--- a/lib/Elastica/Bulk/ResponseSet.php
+++ b/lib/Elastica/Bulk/ResponseSet.php
@@ -101,11 +101,13 @@ public function hasError()
     /**
      * @return \Elastica\Bulk\Response
      */
+    #[\ReturnTypeWillChange]
     public function current()
     {
         return $this->_bulkResponses[$this->key()];
     }
 
+    #[\ReturnTypeWillChange]
     public function next()
     {
         ++$this->_position;
@@ -114,6 +116,7 @@ public function next()
     /**
      * @return int
      */
+    #[\ReturnTypeWillChange]
     public function key()
     {
         return $this->_position;
@@ -122,11 +125,13 @@ public function key()
     /**
      * @return bool
      */
+    #[\ReturnTypeWillChange]
     public function valid()
     {
         return isset($this->_bulkResponses[$this->key()]);
     }
 
+    #[\ReturnTypeWillChange]
     public function rewind()
     {
         $this->_position = 0;
@@ -135,6 +140,7 @@ public function rewind()
     /**
      * @return int
      */
+    #[\ReturnTypeWillChange]
     public function count()
     {
         return count($this->_bulkResponses);
diff --git a/lib/Elastica/Multi/ResultSet.php b/lib/Elastica/Multi/ResultSet.php
index d611a324d3..3a4cb86051 100644
--- a/lib/Elastica/Multi/ResultSet.php
+++ b/lib/Elastica/Multi/ResultSet.php
@@ -82,11 +82,13 @@ public function hasError()
     /**
      * @return \Elastica\ResultSet
      */
+    #[\ReturnTypeWillChange]
     public function current()
     {
         return $this->_resultSets[$this->key()];
     }
 
+    #[\ReturnTypeWillChange]
     public function next()
     {
         ++$this->_position;
@@ -95,6 +97,7 @@ public function next()
     /**
      * @return int
      */
+    #[\ReturnTypeWillChange]
     public function key()
     {
         return $this->_position;
@@ -103,11 +106,13 @@ public function key()
     /**
      * @return bool
      */
+    #[\ReturnTypeWillChange]
     public function valid()
     {
         return isset($this->_resultSets[$this->key()]);
     }
 
+    #[\ReturnTypeWillChange]
     public function rewind()
     {
         $this->_position = 0;
@@ -116,6 +121,7 @@ public function rewind()
     /**
      * @return int
      */
+    #[\ReturnTypeWillChange]
     public function count()
     {
         return count($this->_resultSets);
@@ -126,6 +132,7 @@ public function count()
      *
      * @return bool true on success or false on failure
      */
+    #[\ReturnTypeWillChange]
     public function offsetExists($offset)
     {
         return isset($this->_resultSets[$offset]);
@@ -136,6 +143,7 @@ public function offsetExists($offset)
      *
      * @return mixed can return all value types
      */
+    #[\ReturnTypeWillChange]
     public function offsetGet($offset)
     {
         return $this->_resultSets[$offset] ?? null;
@@ -145,6 +153,7 @@ public function offsetGet($offset)
      * @param mixed $offset
      * @param mixed $value
      */
+    #[\ReturnTypeWillChange]
     public function offsetSet($offset, $value)
     {
         if (is_null($offset)) {
@@ -157,6 +166,7 @@ public function offsetSet($offset, $value)
     /**
      * @param mixed $offset
      */
+    #[\ReturnTypeWillChange]
     public function offsetUnset($offset)
     {
         unset($this->_resultSets[$offset]);
diff --git a/lib/Elastica/NameableInterface.php b/lib/Elastica/NameableInterface.php
index 83b4373736..46e40062a0 100644
--- a/lib/Elastica/NameableInterface.php
+++ b/lib/Elastica/NameableInterface.php
@@ -5,7 +5,6 @@
 /**
  * Interface for named objects.
  *
- *
  * @author Evgeniy Sokolov <ewgraf@gmail.com>
  */
 interface NameableInterface
diff --git a/lib/Elastica/Param.php b/lib/Elastica/Param.php
index 0c765eb0b3..a49e155428 100644
--- a/lib/Elastica/Param.php
+++ b/lib/Elastica/Param.php
@@ -187,6 +187,7 @@ public function getParams()
      *
      * @return int
      */
+    #[\ReturnTypeWillChange]
     public function count()
     {
         return count($this->_params);
diff --git a/lib/Elastica/Query/SpanNear.php b/lib/Elastica/Query/SpanNear.php
index aebc542f9f..5c662d9827 100644
--- a/lib/Elastica/Query/SpanNear.php
+++ b/lib/Elastica/Query/SpanNear.php
@@ -25,9 +25,7 @@ public function __construct($clauses = [], $slop = 1, $inOrder = false)
         if (!empty($clauses)) {
             foreach ($clauses as $clause) {
                 if (!is_subclass_of($clause, AbstractSpanQuery::class)) {
-                    throw new InvalidException(
-                        'Invalid parameter. Has to be array or instance of Elastica\Query\SpanQuery'
-                    );
+                    throw new InvalidException('Invalid parameter. Has to be array or instance of Elastica\Query\SpanQuery');
                 }
             }
         }
diff --git a/lib/Elastica/Query/SpanOr.php b/lib/Elastica/Query/SpanOr.php
index 67113c478a..f350d18771 100644
--- a/lib/Elastica/Query/SpanOr.php
+++ b/lib/Elastica/Query/SpanOr.php
@@ -23,9 +23,7 @@ public function __construct($clauses = [])
         if (!empty($clauses)) {
             foreach ($clauses as $clause) {
                 if (!is_subclass_of($clause, AbstractSpanQuery::class)) {
-                    throw new InvalidException(
-                        'Invalid parameter. Has to be array or instance of Elastica\Query\SpanQuery'
-                    );
+                    throw new InvalidException('Invalid parameter. Has to be array or instance of Elastica\Query\SpanQuery');
                 }
             }
         }
diff --git a/lib/Elastica/QueryBuilder/Facade.php b/lib/Elastica/QueryBuilder/Facade.php
index 3abe04efa6..2b6c05e862 100644
--- a/lib/Elastica/QueryBuilder/Facade.php
+++ b/lib/Elastica/QueryBuilder/Facade.php
@@ -47,17 +47,13 @@ public function __call($name, array $arguments)
     {
         // defined check
         if (false === method_exists($this->_dsl, $name)) {
-            throw new QueryBuilderException(
-                'undefined '.$this->_dsl->getType().' "'.$name.'"'
-            );
+            throw new QueryBuilderException('undefined '.$this->_dsl->getType().' "'.$name.'"');
         }
 
         // version support check
         if (false === $this->_version->supports($name, $this->_dsl->getType())) {
             $reflection = new \ReflectionClass($this->_version);
-            throw new QueryBuilderException(
-                $this->_dsl->getType().' "'.$name.'" in '.$reflection->getShortName().' not supported'
-            );
+            throw new QueryBuilderException($this->_dsl->getType().' "'.$name.'" in '.$reflection->getShortName().' not supported');
         }
 
         return call_user_func_array([$this->_dsl, $name], $arguments);
diff --git a/lib/Elastica/ResultSet.php b/lib/Elastica/ResultSet.php
index e99d03ede8..c780e90d12 100644
--- a/lib/Elastica/ResultSet.php
+++ b/lib/Elastica/ResultSet.php
@@ -219,6 +219,7 @@ public function getQuery()
      *
      * @return int Size of set
      */
+    #[\ReturnTypeWillChange]
     public function count()
     {
         return count($this->_results);
@@ -239,6 +240,7 @@ public function countSuggests()
      *
      * @return \Elastica\Result Set object
      */
+    #[\ReturnTypeWillChange]
     public function current()
     {
         return $this->_results[$this->key()];
@@ -247,6 +249,7 @@ public function current()
     /**
      * Sets pointer (current) to the next item of the set.
      */
+    #[\ReturnTypeWillChange]
     public function next()
     {
         ++$this->_position;
@@ -257,6 +260,7 @@ public function next()
      *
      * @return int Current position
      */
+    #[\ReturnTypeWillChange]
     public function key()
     {
         return $this->_position;
@@ -267,6 +271,7 @@ public function key()
      *
      * @return bool True if object exists
      */
+    #[\ReturnTypeWillChange]
     public function valid()
     {
         return isset($this->_results[$this->key()]);
@@ -275,6 +280,7 @@ public function valid()
     /**
      * Resets position to 0, restarts iterator.
      */
+    #[\ReturnTypeWillChange]
     public function rewind()
     {
         $this->_position = 0;
@@ -289,6 +295,7 @@ public function rewind()
      *
      * @return bool true on success or false on failure
      */
+    #[\ReturnTypeWillChange]
     public function offsetExists($offset)
     {
         return isset($this->_results[$offset]);
@@ -305,6 +312,7 @@ public function offsetExists($offset)
      *
      * @return Result
      */
+    #[\ReturnTypeWillChange]
     public function offsetGet($offset)
     {
         if ($this->offsetExists($offset)) {
@@ -324,6 +332,7 @@ public function offsetGet($offset)
      *
      * @throws Exception\InvalidException
      */
+    #[\ReturnTypeWillChange]
     public function offsetSet($offset, $value)
     {
         if (!($value instanceof Result)) {
@@ -344,6 +353,7 @@ public function offsetSet($offset, $value)
      *
      * @param int $offset
      */
+    #[\ReturnTypeWillChange]
     public function offsetUnset($offset)
     {
         unset($this->_results[$offset]);
diff --git a/lib/Elastica/Scroll.php b/lib/Elastica/Scroll.php
index 8a92fa31ee..04fcd29ee2 100644
--- a/lib/Elastica/Scroll.php
+++ b/lib/Elastica/Scroll.php
@@ -61,6 +61,7 @@ public function __construct(Search $search, $expiryTime = '1m')
      *
      * @return ResultSet
      */
+    #[\ReturnTypeWillChange]
     public function current()
     {
         return $this->_currentResultSet;
@@ -71,6 +72,7 @@ public function current()
      *
      * @see http://php.net/manual/en/iterator.next.php
      */
+    #[\ReturnTypeWillChange]
     public function next()
     {
         if ($this->currentPage < $this->totalPages) {
@@ -95,6 +97,7 @@ public function next()
      *
      * @return string
      */
+    #[\ReturnTypeWillChange]
     public function key()
     {
         return $this->_nextScrollId;
@@ -107,6 +110,7 @@ public function key()
      *
      * @return bool
      */
+    #[\ReturnTypeWillChange]
     public function valid()
     {
         return null !== $this->_nextScrollId;
@@ -117,6 +121,7 @@ public function valid()
      *
      * @see http://php.net/manual/en/iterator.rewind.php
      */
+    #[\ReturnTypeWillChange]
     public function rewind()
     {
         // reset state
diff --git a/test/Elastica/ClientTest.php b/test/Elastica/ClientTest.php
index 9368bfd081..fb0fe8983f 100644
--- a/test/Elastica/ClientTest.php
+++ b/test/Elastica/ClientTest.php
@@ -17,7 +17,6 @@
 use Elastica\Script\Script;
 use Elastica\Test\Base as BaseTest;
 use Elastica\Type;
-use Elasticsearch\Endpoints\Get;
 use Elasticsearch\Endpoints\Indices\Stats;
 use Elasticsearch\Endpoints\Search;
 use Yoast\PHPUnitPolyfills\Polyfills\AssertIsType;