diff --git a/src/config/blockchain.rs b/src/config/blockchain.rs
index bb55bab..25637e2 100644
--- a/src/config/blockchain.rs
+++ b/src/config/blockchain.rs
@@ -2,8 +2,7 @@ use std::path::PathBuf;
 
 use serde::{Deserialize, Serialize};
 
-use crate::ethereum::utils::{parse_caip2_chain_id, ChainIdError};
-use crate::utils::caip2::ChainId;
+use crate::utils::caip2::{ChainId, ChainIdError};
 
 fn default_chain_sync_step() -> u64 { 1000 }
 
@@ -42,7 +41,7 @@ pub struct EthereumConfig {
 
 impl EthereumConfig {
     pub fn try_ethereum_chain_id(&self) -> Result<u32, ChainIdError> {
-        parse_caip2_chain_id(&self.chain_id)
+        self.chain_id.ethereum_chain_id()
     }
 
     pub fn ethereum_chain_id(&self) -> u32 {
diff --git a/src/ethereum/utils.rs b/src/ethereum/utils.rs
index 478b73d..233713a 100644
--- a/src/ethereum/utils.rs
+++ b/src/ethereum/utils.rs
@@ -6,26 +6,6 @@ use web3::{
     types::Address,
 };
 
-use crate::utils::caip2::ChainId;
-
-#[derive(thiserror::Error, Debug)]
-pub enum ChainIdError {
-    #[error("unsupported chain")]
-    UnsupportedChain,
-
-    #[error("invalid EIP155 chain ID")]
-    InvalidEip155ChainId(#[from] std::num::ParseIntError),
-}
-
-/// Parses CAIP-2 chain ID
-pub fn parse_caip2_chain_id(chain_id: &ChainId) -> Result<u32, ChainIdError> {
-    if !chain_id.is_ethereum() {
-        return Err(ChainIdError::UnsupportedChain);
-    };
-    let eth_chain_id: u32 = chain_id.reference.parse()?;
-    Ok(eth_chain_id)
-}
-
 pub fn key_to_ethereum_address(private_key: &SecretKey) -> Address {
     private_key.address()
 }
@@ -42,22 +22,3 @@ pub fn parse_address(address: &str) -> Result<Address, AddressError> {
 pub fn address_to_string(address: Address) -> String {
     format!("{:#x}", address)
 }
-
-#[cfg(test)]
-mod tests {
-    use super::*;
-
-    #[test]
-    fn test_parse_caip2_chain_id() {
-        let chain_id: ChainId = "eip155:1".parse().unwrap();
-        let result = parse_caip2_chain_id(&chain_id).unwrap();
-        assert_eq!(result, 1);
-    }
-
-    #[test]
-    fn test_parse_caip2_chain_id_unsupported() {
-        let chain_id: ChainId = "bip122:000000000019d6689c085ae165831e93".parse().unwrap();
-        let error = parse_caip2_chain_id(&chain_id).err().unwrap();
-        assert!(matches!(error, ChainIdError::UnsupportedChain));
-    }
-}
diff --git a/src/utils/caip2.rs b/src/utils/caip2.rs
index ee40fdb..348b863 100644
--- a/src/utils/caip2.rs
+++ b/src/utils/caip2.rs
@@ -45,18 +45,28 @@ impl ChainId {
     pub fn is_monero(&self) -> bool {
         self.namespace == CAIP2_MONERO_NAMESPACE
     }
+
+    pub fn ethereum_chain_id(&self) -> Result<u32, ChainIdError> {
+        if !self.is_ethereum() {
+            return Err(ChainIdError("namespace is not eip155"));
+        };
+        let chain_id: u32 = self.reference.parse()
+            .map_err(|_| ChainIdError("invalid EIP-155 chain ID"))?;
+        Ok(chain_id)
+    }
 }
 
 #[derive(thiserror::Error, Debug)]
-#[error("Chain ID parse error")]
-pub struct ChainIdError;
+#[error("{0}")]
+pub struct ChainIdError(&'static str);
 
 impl FromStr for ChainId {
     type Err = ChainIdError;
 
     fn from_str(value: &str) -> Result<Self, Self::Err> {
         let caip2_re = Regex::new(CAIP2_RE).unwrap();
-        let caps = caip2_re.captures(value).ok_or(ChainIdError)?;
+        let caps = caip2_re.captures(value)
+            .ok_or(ChainIdError("invalid chain ID"))?;
         let chain_id = Self {
             namespace: caps["namespace"].to_string(),
             reference: caps["reference"].to_string(),
@@ -157,4 +167,18 @@ mod tests {
         let value = "eip155/1/abcde";
         assert!(value.parse::<ChainId>().is_err());
     }
+
+    #[test]
+    fn test_ethereum_chain_id() {
+        let chain_id: ChainId = "eip155:1".parse().unwrap();
+        let result = chain_id.ethereum_chain_id().unwrap();
+        assert_eq!(result, 1);
+    }
+
+    #[test]
+    fn test_ethereum_chain_id_not_ethereum() {
+        let chain_id: ChainId = "bip122:000000000019d6689c085ae165831e93".parse().unwrap();
+        let error = chain_id.ethereum_chain_id().err().unwrap();
+        assert!(matches!(error, ChainIdError("namespace is not eip155")));
+    }
 }