diff --git a/contracts/core/BasePaymaster.sol b/contracts/core/BasePaymaster.sol
index f8aec9d3..efb8b9cb 100644
--- a/contracts/core/BasePaymaster.sol
+++ b/contracts/core/BasePaymaster.sol
@@ -8,7 +8,7 @@ import "@openzeppelin/contracts/utils/introspection/IERC165.sol";
 import "../interfaces/IPaymaster.sol";
 import "../interfaces/IEntryPoint.sol";
 import "./Helpers.sol";
-
+import "./UserOperationLib.sol";
 /**
  * Helper class for creating a paymaster.
  * provides helper methods for staking.
@@ -17,6 +17,10 @@ import "./Helpers.sol";
 abstract contract BasePaymaster is IPaymaster, Ownable {
     IEntryPoint public immutable entryPoint;
 
+    uint256 internal constant PAYMASTER_VALIDATION_GAS_OFFSET = UserOperationLib.PAYMASTER_VALIDATION_GAS_OFFSET;
+    uint256 internal constant PAYMASTER_POSTOP_GAS_OFFSET = UserOperationLib.PAYMASTER_POSTOP_GAS_OFFSET;
+    uint256 internal constant PAYMASTER_DATA_OFFSET = UserOperationLib.PAYMASTER_DATA_OFFSET;
+
     constructor(IEntryPoint _entryPoint) Ownable(msg.sender) {
         _validateEntryPointInterface(_entryPoint);
         entryPoint = _entryPoint;
diff --git a/contracts/samples/LegacyTokenPaymaster.sol b/contracts/samples/LegacyTokenPaymaster.sol
index bc962b95..d673aefc 100644
--- a/contracts/samples/LegacyTokenPaymaster.sol
+++ b/contracts/samples/LegacyTokenPaymaster.sol
@@ -76,7 +76,7 @@ contract LegacyTokenPaymaster is BasePaymaster, ERC20 {
 
         // verificationGasLimit is dual-purposed, as gas limit for postOp. make sure it is high enough
         // make sure that verificationGasLimit is high enough to handle postOp
-        require(uint128(bytes16(userOp.paymasterAndData[UserOperationLib.PAYMASTER_POSTOP_GAS_OFFSET:UserOperationLib.PAYMASTER_DATA_OFFSET])) > COST_OF_POST, "TokenPaymaster: gas too low for postOp");
+        require(uint128(bytes16(userOp.paymasterAndData[PAYMASTER_POSTOP_GAS_OFFSET : PAYMASTER_DATA_OFFSET])) > COST_OF_POST, "TokenPaymaster: gas too low for postOp");
 
         if (userOp.initCode.length != 0) {
             _validateConstructor(userOp);
diff --git a/contracts/samples/TokenPaymaster.sol b/contracts/samples/TokenPaymaster.sol
index 2b40c6cc..00238e1e 100644
--- a/contracts/samples/TokenPaymaster.sol
+++ b/contracts/samples/TokenPaymaster.sol
@@ -121,7 +121,7 @@ contract TokenPaymaster is BasePaymaster, UniswapHelper, OracleHelper {
     override
     returns (bytes memory context, uint256 validationResult) {unchecked {
             uint256 priceMarkup = tokenPaymasterConfig.priceMarkup;
-            uint256 paymasterAndDataLength = userOp.paymasterAndData.length - UserOperationLib.PAYMASTER_DATA_OFFSET;
+            uint256 paymasterAndDataLength = userOp.paymasterAndData.length - PAYMASTER_DATA_OFFSET;
             require(paymasterAndDataLength == 0 || paymasterAndDataLength == 32,
                 "TPM: invalid data length"
             );
@@ -129,7 +129,7 @@ contract TokenPaymaster is BasePaymaster, UniswapHelper, OracleHelper {
         // note: as price is in ether-per-token and we want more tokens increasing it means dividing it by markup
             uint256 cachedPriceWithMarkup = cachedPrice * PRICE_DENOMINATOR / priceMarkup;
             if (paymasterAndDataLength == 32) {
-                uint256 clientSuppliedPrice = uint256(bytes32(userOp.paymasterAndData[UserOperationLib.PAYMASTER_DATA_OFFSET : UserOperationLib.PAYMASTER_DATA_OFFSET + 32]));
+                uint256 clientSuppliedPrice = uint256(bytes32(userOp.paymasterAndData[PAYMASTER_DATA_OFFSET : PAYMASTER_DATA_OFFSET + 32]));
                 if (clientSuppliedPrice < cachedPriceWithMarkup) {
                     // note: smaller number means 'more ether per token'
                     cachedPriceWithMarkup = clientSuppliedPrice;
diff --git a/contracts/samples/VerifyingPaymaster.sol b/contracts/samples/VerifyingPaymaster.sol
index 8bad94c8..6fb13ccc 100644
--- a/contracts/samples/VerifyingPaymaster.sol
+++ b/contracts/samples/VerifyingPaymaster.sol
@@ -23,7 +23,7 @@ contract VerifyingPaymaster is BasePaymaster {
 
     address public immutable verifyingSigner;
 
-    uint256 private constant VALID_TIMESTAMP_OFFSET = UserOperationLib.PAYMASTER_DATA_OFFSET;
+    uint256 private constant VALID_TIMESTAMP_OFFSET = PAYMASTER_DATA_OFFSET;
 
     uint256 private constant SIGNATURE_OFFSET = VALID_TIMESTAMP_OFFSET + 64;
 
@@ -50,7 +50,7 @@ contract VerifyingPaymaster is BasePaymaster {
                 keccak256(userOp.initCode),
                 keccak256(userOp.callData),
                 userOp.accountGasLimits,
-                uint256(bytes32(userOp.paymasterAndData[20 : 52])),
+                uint256(bytes32(userOp.paymasterAndData[PAYMASTER_VALIDATION_GAS_OFFSET : PAYMASTER_DATA_OFFSET])),
                 userOp.preVerificationGas,
                 userOp.maxFeePerGas,
                 userOp.maxPriorityFeePerGas,
diff --git a/contracts/test/TestExpirePaymaster.sol b/contracts/test/TestExpirePaymaster.sol
index de7a374e..a92e3ff2 100644
--- a/contracts/test/TestExpirePaymaster.sol
+++ b/contracts/test/TestExpirePaymaster.sol
@@ -16,7 +16,7 @@ contract TestExpirePaymaster is BasePaymaster {
     internal virtual override view
     returns (bytes memory context, uint256 validationData) {
         (userOp, userOpHash, maxCost);
-        (uint48 validAfter, uint48 validUntil) = abi.decode(userOp.paymasterAndData[UserOperationLib.PAYMASTER_DATA_OFFSET :], (uint48, uint48));
+        (uint48 validAfter, uint48 validUntil) = abi.decode(userOp.paymasterAndData[PAYMASTER_DATA_OFFSET :], (uint48, uint48));
         validationData = _packValidationData(false, validUntil, validAfter);
         context = "";
     }
diff --git a/reports/gas-checker.txt b/reports/gas-checker.txt
index 2b3b6a5f..2af08a79 100644
--- a/reports/gas-checker.txt
+++ b/reports/gas-checker.txt
@@ -22,11 +22,11 @@
 ╟────────────────────────────────┼───────┼───────────────┼────────────────┼─────────────────────╢
 ║ simple paymaster               │     1 │         89079 │                │                     ║
 ╟────────────────────────────────┼───────┼───────────────┼────────────────┼─────────────────────╢
-║ simple paymaster with diff     │     2 │               │          43963 │               14984 ║
+║ simple paymaster with diff     │     2 │               │          43987 │               15008 ║
 ╟────────────────────────────────┼───────┼───────────────┼────────────────┼─────────────────────╢
-║ simple paymaster               │    10 │        485071 │                │                     ║
+║ simple paymaster               │    10 │        485083 │                │                     ║
 ╟────────────────────────────────┼───────┼───────────────┼────────────────┼─────────────────────╢
-║ simple paymaster with diff     │    11 │               │          44017 │               15038 ║
+║ simple paymaster with diff     │    11 │               │          44005 │               15026 ║
 ╟────────────────────────────────┼───────┼───────────────┼────────────────┼─────────────────────╢
 ║ big tx 5k                      │     1 │        183735 │                │                     ║
 ╟────────────────────────────────┼───────┼───────────────┼────────────────┼─────────────────────╢
@@ -36,11 +36,11 @@
 ╟────────────────────────────────┼───────┼───────────────┼────────────────┼─────────────────────╢
 ║ big tx - diff from previous    │    11 │               │         145440 │               20216 ║
 ╟────────────────────────────────┼───────┼───────────────┼────────────────┼─────────────────────╢
-║ paymaster+postOp               │     1 │         90907 │                │                     ║
+║ paymaster+postOp               │     1 │         90895 │                │                     ║
 ╟────────────────────────────────┼───────┼───────────────┼────────────────┼─────────────────────╢
-║ paymaster+postOp with diff     │     2 │               │          45814 │               16835 ║
+║ paymaster+postOp with diff     │     2 │               │          45850 │               16871 ║
 ╟────────────────────────────────┼───────┼───────────────┼────────────────┼─────────────────────╢
-║ paymaster+postOp               │    10 │        503383 │                │                     ║
+║ paymaster+postOp               │    10 │        503503 │                │                     ║
 ╟────────────────────────────────┼───────┼───────────────┼────────────────┼─────────────────────╢
 ║ paymaster+postOp with diff     │    11 │               │          45851 │               16872 ║
 ╟────────────────────────────────┼───────┼───────────────┼────────────────┼─────────────────────╢
@@ -50,6 +50,6 @@
 ╟────────────────────────────────┼───────┼───────────────┼────────────────┼─────────────────────╢
 ║ token paymaster                │    10 │        816150 │                │                     ║
 ╟────────────────────────────────┼───────┼───────────────┼────────────────┼─────────────────────╢
-║ token paymaster with diff      │    11 │               │          74094 │               45115 ║
+║ token paymaster with diff      │    11 │               │          74106 │               45127 ║
 ╚════════════════════════════════╧═══════╧═══════════════╧════════════════╧═════════════════════╝