diff --git a/UPGRADE.md b/UPGRADE.md
index 3a0827a72c8..e671789cb78 100644
--- a/UPGRADE.md
+++ b/UPGRADE.md
@@ -8,6 +8,10 @@ awareness about deprecated code.
 
 # Upgrade to 4.0
 
+## BC BREAK: removed default precision and scale of decimal columns.
+
+The DBAL no longer provides default values for precision and scale of decimal columns.
+
 ## BC BREAK: a non-empty WHERE clause is not enforced in data manipulation `Connection` methods.
 
 The `Connection::update()` and `::delete()` methods no longer enforce a non-empty WHERE clause. If modification
diff --git a/src/Exception/ColumnPrecisionRequired.php b/src/Exception/ColumnPrecisionRequired.php
new file mode 100644
index 00000000000..a006345ffd3
--- /dev/null
+++ b/src/Exception/ColumnPrecisionRequired.php
@@ -0,0 +1,18 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Doctrine\DBAL\Exception;
+
+use Doctrine\DBAL\Exception;
+
+/**
+ * @psalm-immutable
+ */
+final class ColumnPrecisionRequired extends Exception
+{
+    public static function new(): self
+    {
+        return new self('Column precision is not specified');
+    }
+}
diff --git a/src/Exception/ColumnScaleRequired.php b/src/Exception/ColumnScaleRequired.php
new file mode 100644
index 00000000000..b9b6b2ed84a
--- /dev/null
+++ b/src/Exception/ColumnScaleRequired.php
@@ -0,0 +1,18 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Doctrine\DBAL\Exception;
+
+use Doctrine\DBAL\Exception;
+
+/**
+ * @psalm-immutable
+ */
+final class ColumnScaleRequired extends Exception
+{
+    public static function new(): self
+    {
+        return new self('Column scale is not specified');
+    }
+}
diff --git a/src/Platforms/AbstractPlatform.php b/src/Platforms/AbstractPlatform.php
index 299dd3c40f3..a932bd77c11 100644
--- a/src/Platforms/AbstractPlatform.php
+++ b/src/Platforms/AbstractPlatform.php
@@ -17,6 +17,8 @@
 use Doctrine\DBAL\Events;
 use Doctrine\DBAL\Exception;
 use Doctrine\DBAL\Exception\ColumnLengthRequired;
+use Doctrine\DBAL\Exception\ColumnPrecisionRequired;
+use Doctrine\DBAL\Exception\ColumnScaleRequired;
 use Doctrine\DBAL\LockMode;
 use Doctrine\DBAL\Platforms\Exception\NoColumnsSpecifiedForTable;
 use Doctrine\DBAL\Platforms\Exception\NotSupported;
@@ -36,7 +38,6 @@
 use Doctrine\DBAL\Types;
 use Doctrine\DBAL\Types\Exception\TypeNotFound;
 use Doctrine\DBAL\Types\Type;
-use Doctrine\Deprecations\Deprecation;
 use InvalidArgumentException;
 use UnexpectedValueException;
 
@@ -1575,40 +1576,21 @@ public function getColumnDeclarationSQL(string $name, array $column): string
      * Returns the SQL snippet that declares a floating point column of arbitrary precision.
      *
      * @param mixed[] $column
+     *
+     * @throws ColumnPrecisionRequired
+     * @throws ColumnScaleRequired
      */
     public function getDecimalTypeDeclarationSQL(array $column): string
     {
-        if (empty($column['precision'])) {
-            if (! isset($column['precision'])) {
-                Deprecation::trigger(
-                    'doctrine/dbal',
-                    'https://github.com/doctrine/dbal/pull/5637',
-                    'Relying on the default decimal column precision is deprecated'
-                        . ', specify the precision explicitly.',
-                );
-            }
-
-            $precision = 10;
-        } else {
-            $precision = $column['precision'];
+        if (! isset($column['precision'])) {
+            throw ColumnPrecisionRequired::new();
         }
 
-        if (empty($column['scale'])) {
-            if (! isset($column['scale'])) {
-                Deprecation::trigger(
-                    'doctrine/dbal',
-                    'https://github.com/doctrine/dbal/pull/5637',
-                    'Relying on the default decimal column scale is deprecated'
-                        . ', specify the scale explicitly.',
-                );
-            }
-
-            $scale = 0;
-        } else {
-            $scale = $column['scale'];
+        if (! isset($column['scale'])) {
+            throw ColumnScaleRequired::new();
         }
 
-        return 'NUMERIC(' . $precision . ', ' . $scale . ')';
+        return 'NUMERIC(' . $column['precision'] . ', ' . $column['scale'] . ')';
     }
 
     /**
diff --git a/src/Schema/Comparator.php b/src/Schema/Comparator.php
index ab238f419ec..64df1da0775 100644
--- a/src/Schema/Comparator.php
+++ b/src/Schema/Comparator.php
@@ -471,7 +471,7 @@ public function diffColumn(Column $column1, Column $column2): array
                 $changedProperties[] = 'fixed';
             }
         } elseif ($properties1['type'] instanceof Types\DecimalType) {
-            if (($properties1['precision'] ?? 10) !== ($properties2['precision'] ?? 10)) {
+            if ($properties1['precision'] !== $properties2['precision']) {
                 $changedProperties[] = 'precision';
             }
 
diff --git a/tests/Functional/Schema/MySQLSchemaManagerTest.php b/tests/Functional/Schema/MySQLSchemaManagerTest.php
index 1a7f22d63aa..3c533c6601d 100644
--- a/tests/Functional/Schema/MySQLSchemaManagerTest.php
+++ b/tests/Functional/Schema/MySQLSchemaManagerTest.php
@@ -344,8 +344,16 @@ public function testListDecimalTypeColumns(): void
         $tableName = 'test_list_decimal_columns';
         $table     = new Table($tableName);
 
-        $table->addColumn('col', 'decimal');
-        $table->addColumn('col_unsigned', 'decimal', ['unsigned' => true]);
+        $table->addColumn('col', 'decimal', [
+            'precision' => 10,
+            'scale' => 6,
+        ]);
+
+        $table->addColumn('col_unsigned', 'decimal', [
+            'precision' => 10,
+            'scale' => 6,
+            'unsigned' => true,
+        ]);
 
         $this->dropAndCreateTable($table);
 
diff --git a/tests/Functional/Schema/PostgreSQLSchemaManagerTest.php b/tests/Functional/Schema/PostgreSQLSchemaManagerTest.php
index bfa1a205408..957822cd56b 100644
--- a/tests/Functional/Schema/PostgreSQLSchemaManagerTest.php
+++ b/tests/Functional/Schema/PostgreSQLSchemaManagerTest.php
@@ -370,7 +370,11 @@ public function testListNegativeColumnDefaultValue(): void
         $table->addColumn('col_integer', 'integer', ['default' => -1]);
         $table->addColumn('col_bigint', 'bigint', ['default' => -1]);
         $table->addColumn('col_float', 'float', ['default' => -1.1]);
-        $table->addColumn('col_decimal', 'decimal', ['default' => -1.1]);
+        $table->addColumn('col_decimal', 'decimal', [
+            'precision' => 2,
+            'scale' => 1,
+            'default' => -1.1,
+        ]);
         $table->addColumn('col_string', 'string', ['default' => '(-1)']);
 
         $this->dropAndCreateTable($table);
diff --git a/tests/Functional/Schema/SQLServerSchemaManagerTest.php b/tests/Functional/Schema/SQLServerSchemaManagerTest.php
index 8017e1704e8..6478a3ae4d3 100644
--- a/tests/Functional/Schema/SQLServerSchemaManagerTest.php
+++ b/tests/Functional/Schema/SQLServerSchemaManagerTest.php
@@ -25,7 +25,7 @@ public function testDropColumnConstraints(): void
     {
         $table = new Table('sqlsrv_drop_column');
         $table->addColumn('id', 'integer');
-        $table->addColumn('todrop', 'decimal', ['default' => 10.2]);
+        $table->addColumn('todrop', 'integer', ['default' => 10]);
 
         $this->schemaManager->createTable($table);
 
@@ -33,7 +33,7 @@ public function testDropColumnConstraints(): void
             'sqlsrv_drop_column',
             [],
             [],
-            ['todrop' => new Column('todrop', Type::getType('decimal'))],
+            ['todrop' => new Column('todrop', Type::getType('integer'))],
         );
 
         $this->schemaManager->alterTable($diff);
diff --git a/tests/Platforms/AbstractMySQLPlatformTestCase.php b/tests/Platforms/AbstractMySQLPlatformTestCase.php
index 6e64e230674..6fe0ee1e8f6 100644
--- a/tests/Platforms/AbstractMySQLPlatformTestCase.php
+++ b/tests/Platforms/AbstractMySQLPlatformTestCase.php
@@ -688,14 +688,9 @@ protected function getGeneratesAlterTableRenameIndexUsedByForeignKeySQL(): array
      */
     public static function getGeneratesDecimalTypeDeclarationSQL(): iterable
     {
-        return [
-            [[], 'NUMERIC(10, 0)'],
-            [['unsigned' => true], 'NUMERIC(10, 0) UNSIGNED'],
-            [['unsigned' => false], 'NUMERIC(10, 0)'],
-            [['precision' => 5], 'NUMERIC(5, 0)'],
-            [['scale' => 5], 'NUMERIC(10, 5)'],
-            [['precision' => 8, 'scale' => 2], 'NUMERIC(8, 2)'],
-        ];
+        yield [['precision' => 10, 'scale' => 8, 'unsigned' => true], 'NUMERIC(10, 8) UNSIGNED'];
+
+        yield from parent::getGeneratesDecimalTypeDeclarationSQL();
     }
 
     /**
diff --git a/tests/Platforms/AbstractPlatformTestCase.php b/tests/Platforms/AbstractPlatformTestCase.php
index c40a9c91371..aa84489559f 100644
--- a/tests/Platforms/AbstractPlatformTestCase.php
+++ b/tests/Platforms/AbstractPlatformTestCase.php
@@ -7,6 +7,8 @@
 use Doctrine\Common\EventManager;
 use Doctrine\DBAL\Events;
 use Doctrine\DBAL\Exception;
+use Doctrine\DBAL\Exception\ColumnPrecisionRequired;
+use Doctrine\DBAL\Exception\ColumnScaleRequired;
 use Doctrine\DBAL\Platforms\AbstractPlatform;
 use Doctrine\DBAL\Schema\Column;
 use Doctrine\DBAL\Schema\ColumnDiff;
@@ -739,6 +741,18 @@ public function getExpectedVariableLengthBinaryTypeDeclarationSQLWithLength(): s
         return 'VARBINARY(16)';
     }
 
+    public function testGetDecimalTypeDeclarationSQLNoPrecision(): void
+    {
+        $this->expectException(ColumnPrecisionRequired::class);
+        $this->platform->getDecimalTypeDeclarationSQL(['scale' => 2]);
+    }
+
+    public function testGetDecimalTypeDeclarationSQLNoScale(): void
+    {
+        $this->expectException(ColumnScaleRequired::class);
+        $this->platform->getDecimalTypeDeclarationSQL(['precision' => 10]);
+    }
+
     public function testReturnsJsonTypeDeclarationSQL(): void
     {
         $column = [
@@ -1207,17 +1221,11 @@ public function testGeneratesDecimalTypeDeclarationSQL(array $column, string $ex
         self::assertSame($expectedSql, $this->platform->getDecimalTypeDeclarationSQL($column));
     }
 
-    /** @return mixed[][] */
+    /** @return iterable<array{array<string,mixed>,string}> */
     public static function getGeneratesDecimalTypeDeclarationSQL(): iterable
     {
-        return [
-            [[], 'NUMERIC(10, 0)'],
-            [['unsigned' => true], 'NUMERIC(10, 0)'],
-            [['unsigned' => false], 'NUMERIC(10, 0)'],
-            [['precision' => 5], 'NUMERIC(5, 0)'],
-            [['scale' => 5], 'NUMERIC(10, 5)'],
-            [['precision' => 8, 'scale' => 2], 'NUMERIC(8, 2)'],
-        ];
+        yield [['precision' => 10, 'scale' => 0], 'NUMERIC(10, 0)'];
+        yield [['precision' => 8, 'scale' => 2], 'NUMERIC(8, 2)'];
     }
 
     /**