diff --git a/mm2src/coins/eth/eth_swap_v2/eth_maker_swap_v2.rs b/mm2src/coins/eth/eth_swap_v2/eth_maker_swap_v2.rs
index 992e053951..b8aa3aaf71 100644
--- a/mm2src/coins/eth/eth_swap_v2/eth_maker_swap_v2.rs
+++ b/mm2src/coins/eth/eth_swap_v2/eth_maker_swap_v2.rs
@@ -18,6 +18,15 @@ use web3::types::TransactionId;
 const ETH_MAKER_PAYMENT: &str = "ethMakerPayment";
 const ERC20_MAKER_PAYMENT: &str = "erc20MakerPayment";
 
+/// state index for `MakerPayment` structure from `EtomicSwapMakerV2.sol`
+///
+///     struct MakerPayment {
+///         bytes20 paymentHash;
+///         uint32 paymentLockTime;
+///         MakerPaymentState state;
+///     }
+const MAKER_PAYMENT_STATE_INDX: usize = 2;
+
 struct MakerPaymentArgs {
     taker_address: Address,
     taker_secret_hash: [u8; 32],
@@ -127,7 +136,7 @@ impl EthCoin {
                 Token::FixedBytes(swap_id.clone()),
                 &MAKER_SWAP_V2,
                 EthPaymentType::MakerPayments,
-                2,
+                MAKER_PAYMENT_STATE_INDX,
             )
             .await?;
 
diff --git a/mm2src/coins/eth/eth_swap_v2/eth_taker_swap_v2.rs b/mm2src/coins/eth/eth_swap_v2/eth_taker_swap_v2.rs
index 997cce1eb5..621d9df743 100644
--- a/mm2src/coins/eth/eth_swap_v2/eth_taker_swap_v2.rs
+++ b/mm2src/coins/eth/eth_swap_v2/eth_taker_swap_v2.rs
@@ -21,6 +21,16 @@ const ETH_TAKER_PAYMENT: &str = "ethTakerPayment";
 const ERC20_TAKER_PAYMENT: &str = "erc20TakerPayment";
 const TAKER_PAYMENT_APPROVE: &str = "takerPaymentApprove";
 
+/// state index for `TakerPayment` structure from `EtomicSwapTakerV2.sol`
+///
+///     struct TakerPayment {
+///         bytes20 paymentHash;
+///         uint32 preApproveLockTime;
+///         uint32 paymentLockTime;
+///         TakerPaymentState state;
+///     }
+const TAKER_PAYMENT_STATE_INDX: usize = 3;
+
 struct TakerFundingArgs {
     dex_fee: U256,
     payment_amount: U256,
@@ -147,7 +157,7 @@ impl EthCoin {
                 Token::FixedBytes(swap_id.clone()),
                 &TAKER_SWAP_V2,
                 EthPaymentType::TakerPayments,
-                3,
+                TAKER_PAYMENT_STATE_INDX,
             )
             .await?;
 
@@ -220,7 +230,7 @@ impl EthCoin {
                 decoded[0].clone(),
                 &TAKER_SWAP_V2,
                 EthPaymentType::TakerPayments,
-                3,
+                TAKER_PAYMENT_STATE_INDX,
             )
             .await
         );
@@ -371,7 +381,7 @@ impl EthCoin {
                 decoded[0].clone(), // id from takerPaymentApprove
                 &TAKER_SWAP_V2,
                 EthPaymentType::TakerPayments,
-                3,
+                TAKER_PAYMENT_STATE_INDX,
             )
             .await
             .map_err(|e| SearchForFundingSpendErr::Internal(ERRL!("{}", e)))?;
@@ -403,7 +413,7 @@ impl EthCoin {
                 decoded[0].clone(),
                 &TAKER_SWAP_V2,
                 EthPaymentType::TakerPayments,
-                3,
+                TAKER_PAYMENT_STATE_INDX,
             )
             .await
         );
@@ -446,7 +456,7 @@ impl EthCoin {
                     decoded[0].clone(), // id from spendTakerPayment
                     &TAKER_SWAP_V2,
                     EthPaymentType::TakerPayments,
-                    3,
+                    TAKER_PAYMENT_STATE_INDX,
                 )
                 .await?;
             if taker_status == U256::from(TakerPaymentStateV2::MakerSpent as u8) {