diff --git a/Changelog.md b/Changelog.md
index 82a16fe0d..e45646c91 100644
--- a/Changelog.md
+++ b/Changelog.md
@@ -5,6 +5,7 @@ Breaking changes:
  * Constructors should not have visibility.
  * Deprecated dot syntax for `value` and `gas`.
  * Deprecated the identifier `now`.
+ * Disallow `gwei` as identifier.
  * JSON AST: Removes members with ``null`` value from JSON output.
  * Parser: NatSpec comments on variables are only allowed for public state variables.
  * Type Checker: Disallow shifts by signed types.
diff --git a/liblangutil/Token.h b/liblangutil/Token.h
index d887e3901..cea102f0f 100644
--- a/liblangutil/Token.h
+++ b/liblangutil/Token.h
@@ -196,6 +196,7 @@ namespace solidity::langutil
 	\
 	/* Ether subdenominations */                                       \
 	K(SubWei, "wei", 0)                                                \
+	K(SubGwei, "gwei", 0)                                              \
 	K(SubEther, "ether", 0)                                            \
 	K(SubSecond, "seconds", 0)                                         \
 	K(SubMinute, "minutes", 0)                                         \
@@ -230,7 +231,6 @@ namespace solidity::langutil
 	\
 	/* Identifiers (not keywords or future reserved words). */         \
 	T(Identifier, nullptr, 0)                                          \
-	T(SubGwei, "gwei", 0)                                              \
 	\
 	/* Keywords reserved for future use. */                            \
 	K(After, "after", 0)                                               \
@@ -311,7 +311,7 @@ namespace TokenTraits
 			|| op == Token::Pure || op == Token::View || op == Token::Payable;
 	}
 
-	constexpr bool isEtherSubdenomination(Token op) { return op == Token::SubWei || op == Token::SubEther; }
+	constexpr bool isEtherSubdenomination(Token op) { return op >= Token::SubWei && op <= Token::SubEther; }
 	constexpr bool isTimeSubdenomination(Token op) { return op == Token::SubSecond || op == Token::SubMinute || op == Token::SubHour || op == Token::SubDay || op == Token::SubWeek || op == Token::SubYear; }
 	constexpr bool isReservedKeyword(Token op) { return (Token::After <= op && op <= Token::Unchecked); }
 
diff --git a/libsolidity/parsing/Parser.cpp b/libsolidity/parsing/Parser.cpp
index 819d18a79..ab8180dc7 100644
--- a/libsolidity/parsing/Parser.cpp
+++ b/libsolidity/parsing/Parser.cpp
@@ -1825,16 +1825,11 @@ ASTPointer<Expression> Parser::parsePrimaryExpression()
 		expression = nodeFactory.createNode<Literal>(token, getLiteralAndAdvance());
 		break;
 	case Token::Number:
-		if (
-			(m_scanner->peekNextToken() == Token::Identifier && m_scanner->peekLiteral() == "gwei") ||
-			TokenTraits::isEtherSubdenomination(m_scanner->peekNextToken())
-		)
+		if (TokenTraits::isEtherSubdenomination(m_scanner->peekNextToken()))
 		{
 			ASTPointer<ASTString> literal = getLiteralAndAdvance();
 			nodeFactory.markEndPosition();
-			Token actualToken = m_scanner->currentToken() == Token::Identifier ? Token::SubGwei : m_scanner->currentToken();
-
-			Literal::SubDenomination subdenomination = static_cast<Literal::SubDenomination>(actualToken);
+			Literal::SubDenomination subdenomination = static_cast<Literal::SubDenomination>(m_scanner->currentToken());
 			m_scanner->next();
 			expression = nodeFactory.createNode<Literal>(token, literal, subdenomination);
 		}
diff --git a/test/libsolidity/SolidityScanner.cpp b/test/libsolidity/SolidityScanner.cpp
index 93e44a5bf..5b83778ba 100644
--- a/test/libsolidity/SolidityScanner.cpp
+++ b/test/libsolidity/SolidityScanner.cpp
@@ -430,7 +430,7 @@ BOOST_AUTO_TEST_CASE(ether_subdenominations)
 {
 	Scanner scanner(CharStream("wei gwei ether", ""));
 	BOOST_CHECK_EQUAL(scanner.currentToken(), Token::SubWei);
-	BOOST_CHECK_EQUAL(scanner.next(), Token::Identifier);
+	BOOST_CHECK_EQUAL(scanner.next(), Token::SubGwei);
 	BOOST_CHECK_EQUAL(scanner.next(), Token::SubEther);
 }
 
diff --git a/test/libsolidity/semanticTests/literals/gwei.sol b/test/libsolidity/semanticTests/literals/gwei.sol
index 7762021dc..54870040f 100644
--- a/test/libsolidity/semanticTests/literals/gwei.sol
+++ b/test/libsolidity/semanticTests/literals/gwei.sol
@@ -1,7 +1,7 @@
 contract C {
-	uint constant gwei = 1 gwei;
+	uint constant x = 1 gwei;
 
-	function f() public view returns(uint) { return gwei; }
+	function f() public view returns(uint) { return x; }
 }
 // ====
 // compileViaYul: also
diff --git a/test/libsolidity/syntaxTests/denominations/gwei.sol b/test/libsolidity/syntaxTests/denominations/gwei.sol
deleted file mode 100644
index 5bc5edb3d..000000000
--- a/test/libsolidity/syntaxTests/denominations/gwei.sol
+++ /dev/null
@@ -1,3 +0,0 @@
-contract C {
-	uint constant gwei = 1 gwei;
-}
diff --git a/test/libsolidity/syntaxTests/denominations/gwei_as_identifier.sol b/test/libsolidity/syntaxTests/denominations/gwei_as_identifier.sol
new file mode 100644
index 000000000..43fde5ed7
--- /dev/null
+++ b/test/libsolidity/syntaxTests/denominations/gwei_as_identifier.sol
@@ -0,0 +1,5 @@
+contract C {
+	uint constant gwei = 1;
+}
+// ----
+// ParserError 2314: (28-32): Expected identifier but got 'gwei'