diff --git a/tests/serialization_tests/tests/u_message_ser.rs b/tests/serialization_tests/tests/u_message_ser.rs
index cef7e42d0e3c..82b24889a8cd 100644
--- a/tests/serialization_tests/tests/u_message_ser.rs
+++ b/tests/serialization_tests/tests/u_message_ser.rs
@@ -12,7 +12,7 @@ use serde::Deserialize;
 use std::fs::File;
 use std::io::prelude::*;
 use std::str::FromStr;
-use vm::{MethodNum, Serialized};
+use vm::Serialized;
 
 #[derive(Debug, Deserialize)]
 struct MessageVector {
@@ -41,7 +41,7 @@ impl From<MessageVector> for UnsignedMessage {
             .from(Address::from_str(&vector.from).unwrap())
             .sequence(vector.nonce)
             .value(vector.value.parse().unwrap())
-            .method_num(MethodNum::new(vector.method))
+            .method_num(vector.method)
             .params(Serialized::new(base64::decode(&vector.params).unwrap()))
             .gas_limit(vector.gas_limit)
             .gas_price(vector.gas_price.parse().unwrap())
diff --git a/vm/actor/src/builtin/account/mod.rs b/vm/actor/src/builtin/account/mod.rs
index ddf18baed7b3..ec5c98331f80 100644
--- a/vm/actor/src/builtin/account/mod.rs
+++ b/vm/actor/src/builtin/account/mod.rs
@@ -14,6 +14,7 @@ use vm::{ActorError, ExitCode, MethodNum, Serialized, METHOD_CONSTRUCTOR};
 
 /// Account actor methods available
 #[derive(FromPrimitive)]
+#[repr(u64)]
 pub enum Method {
     Constructor = METHOD_CONSTRUCTOR,
     PubkeyAddress = 2,
@@ -22,7 +23,7 @@ pub enum Method {
 impl Method {
     /// Converts a method number into a Method enum
     fn from_method_num(m: MethodNum) -> Option<Method> {
-        FromPrimitive::from_u64(u64::from(m))
+        FromPrimitive::from_u64(m)
     }
 }
 
diff --git a/vm/actor/src/builtin/cron/mod.rs b/vm/actor/src/builtin/cron/mod.rs
index 4459541e670a..c9da63df8347 100644
--- a/vm/actor/src/builtin/cron/mod.rs
+++ b/vm/actor/src/builtin/cron/mod.rs
@@ -16,6 +16,7 @@ use vm::{ActorError, ExitCode, MethodNum, Serialized, TokenAmount, METHOD_CONSTR
 
 /// Cron actor methods available
 #[derive(FromPrimitive)]
+#[repr(u64)]
 pub enum Method {
     Constructor = METHOD_CONSTRUCTOR,
     EpochTick = 2,
@@ -24,7 +25,7 @@ pub enum Method {
 impl Method {
     /// Converts a method number into an Method enum
     fn from_method_num(m: MethodNum) -> Option<Method> {
-        FromPrimitive::from_u64(u64::from(m))
+        FromPrimitive::from_u64(m)
     }
 }
 
diff --git a/vm/actor/src/builtin/init/mod.rs b/vm/actor/src/builtin/init/mod.rs
index f7a65e876c54..76fbea52e29b 100644
--- a/vm/actor/src/builtin/init/mod.rs
+++ b/vm/actor/src/builtin/init/mod.rs
@@ -22,6 +22,7 @@ use vm::{ActorError, ExitCode, MethodNum, Serialized, METHOD_CONSTRUCTOR};
 
 /// Init actor methods available
 #[derive(FromPrimitive)]
+#[repr(u64)]
 pub enum Method {
     Constructor = METHOD_CONSTRUCTOR,
     Exec = 2,
@@ -30,7 +31,7 @@ pub enum Method {
 impl Method {
     /// Converts a method number into an Method enum
     fn from_method_num(m: MethodNum) -> Option<Method> {
-        FromPrimitive::from_u64(u64::from(m))
+        FromPrimitive::from_u64(m)
     }
 }
 
@@ -102,7 +103,7 @@ impl Actor {
         // Invoke constructor
         rt.send::<Ipld>(
             &id_address,
-            MethodNum::new(METHOD_CONSTRUCTOR as u64),
+            METHOD_CONSTRUCTOR,
             &params.constructor_params,
             rt.message().value(),
         )
diff --git a/vm/actor/src/builtin/init/state.rs b/vm/actor/src/builtin/init/state.rs
index c0caedeec5e3..189f9e435916 100644
--- a/vm/actor/src/builtin/init/state.rs
+++ b/vm/actor/src/builtin/init/state.rs
@@ -41,7 +41,7 @@ impl State {
         map.set(addr.hash_key(), id)?;
         self.address_map = map.flush()?;
 
-        Ok(Address::new_id(id.0).expect("Id Address should be created without Error"))
+        Ok(Address::new_id(id).expect("Id Address should be created without Error"))
     }
 
     /// ResolveAddress resolves an address to an ID-address, if possible.
@@ -66,7 +66,7 @@ impl State {
             .get(&addr.hash_key())?
             .ok_or_else(|| "Address not found".to_owned())?;
 
-        Ok(Address::new_id(actor_id.0).map_err(|e| e.to_string())?)
+        Ok(Address::new_id(actor_id).map_err(|e| e.to_string())?)
     }
 }
 
diff --git a/vm/actor/src/builtin/multisig/mod.rs b/vm/actor/src/builtin/multisig/mod.rs
index 6a8980c18881..c3a1e890fb66 100644
--- a/vm/actor/src/builtin/multisig/mod.rs
+++ b/vm/actor/src/builtin/multisig/mod.rs
@@ -18,6 +18,7 @@ use vm::{ActorError, ExitCode, MethodNum, Serialized, TokenAmount, METHOD_CONSTR
 
 /// Multisig actor methods available
 #[derive(FromPrimitive)]
+#[repr(u64)]
 pub enum Method {
     Constructor = METHOD_CONSTRUCTOR,
     Propose = 2,
@@ -34,7 +35,7 @@ pub enum Method {
 impl Method {
     /// Converts a method number into a Method enum
     fn from_method_num(m: MethodNum) -> Option<Method> {
-        FromPrimitive::from_u64(u64::from(m))
+        FromPrimitive::from_u64(m)
     }
 }
 
diff --git a/vm/actor/src/builtin/paych/mod.rs b/vm/actor/src/builtin/paych/mod.rs
index fe0be38fdd20..ebf8bed1e653 100644
--- a/vm/actor/src/builtin/paych/mod.rs
+++ b/vm/actor/src/builtin/paych/mod.rs
@@ -23,6 +23,7 @@ use vm::{
 
 /// Payment Channel actor methods available
 #[derive(FromPrimitive)]
+#[repr(u64)]
 pub enum Method {
     Constructor = METHOD_CONSTRUCTOR,
     UpdateChannelState = 2,
@@ -33,7 +34,7 @@ pub enum Method {
 impl Method {
     /// Converts a method number into an Method enum
     fn from_method_num(m: MethodNum) -> Option<Method> {
-        FromPrimitive::from_u64(u64::from(m))
+        FromPrimitive::from_u64(m)
     }
 }
 
@@ -299,20 +300,10 @@ impl Actor {
             })?;
 
         // send remaining balance to `from`
-        rt.send::<Ipld>(
-            &st.from,
-            MethodNum(METHOD_SEND as u64),
-            &Serialized::default(),
-            &rem_bal,
-        )?;
+        rt.send::<Ipld>(&st.from, METHOD_SEND, &Serialized::default(), &rem_bal)?;
 
         // send ToSend to `to`
-        rt.send::<Ipld>(
-            &st.to,
-            MethodNum(METHOD_SEND as u64),
-            &Serialized::default(),
-            &st.to_send,
-        )?;
+        rt.send::<Ipld>(&st.to, METHOD_SEND, &Serialized::default(), &st.to_send)?;
 
         rt.transaction(|st: &mut State| {
             st.to_send = TokenAmount::from(0u8);
diff --git a/vm/actor/src/builtin/power/mod.rs b/vm/actor/src/builtin/power/mod.rs
index 247961e4da42..cb54c110f310 100644
--- a/vm/actor/src/builtin/power/mod.rs
+++ b/vm/actor/src/builtin/power/mod.rs
@@ -13,6 +13,7 @@ use vm::{ActorError, ExitCode, MethodNum, Serialized, METHOD_CONSTRUCTOR};
 
 /// Storage power actor methods available
 #[derive(FromPrimitive)]
+#[repr(u64)]
 pub enum Method {
     /// Constructor for Storage Power Actor
     Constructor = METHOD_CONSTRUCTOR,
@@ -35,7 +36,7 @@ pub enum Method {
 impl Method {
     /// Converts a method number into an Method enum
     fn from_method_num(m: MethodNum) -> Option<Method> {
-        FromPrimitive::from_u64(u64::from(m))
+        FromPrimitive::from_u64(m)
     }
 }
 
diff --git a/vm/actor/src/builtin/reward/mod.rs b/vm/actor/src/builtin/reward/mod.rs
index 1da727943077..ff7c20ffa0af 100644
--- a/vm/actor/src/builtin/reward/mod.rs
+++ b/vm/actor/src/builtin/reward/mod.rs
@@ -14,6 +14,7 @@ use vm::{ActorError, ExitCode, MethodNum, Serialized, METHOD_CONSTRUCTOR};
 
 /// Reward actor methods available
 #[derive(FromPrimitive)]
+#[repr(u64)]
 pub enum Method {
     Constructor = METHOD_CONSTRUCTOR,
     AwardBlockReward = 2,
@@ -23,7 +24,7 @@ pub enum Method {
 impl Method {
     /// Converts a method number into an Method enum
     fn from_method_num(m: MethodNum) -> Option<Method> {
-        FromPrimitive::from_u64(u64::from(m))
+        FromPrimitive::from_u64(m)
     }
 }
 
diff --git a/vm/actor/src/builtin/singletons.rs b/vm/actor/src/builtin/singletons.rs
index b06904b455c9..742d3591e723 100644
--- a/vm/actor/src/builtin/singletons.rs
+++ b/vm/actor/src/builtin/singletons.rs
@@ -16,4 +16,4 @@ lazy_static! {
 }
 
 /// Defines first available ID address after builtin actors
-pub const FIRST_NON_SINGLETON_ADDR: ActorID = ActorID(100);
+pub const FIRST_NON_SINGLETON_ADDR: ActorID = 100;
diff --git a/vm/actor/src/builtin/system/mod.rs b/vm/actor/src/builtin/system/mod.rs
index 2752c1abe49c..8d72441ae8e9 100644
--- a/vm/actor/src/builtin/system/mod.rs
+++ b/vm/actor/src/builtin/system/mod.rs
@@ -12,6 +12,7 @@ use vm::{ActorError, ExitCode, MethodNum, Serialized, METHOD_CONSTRUCTOR};
 
 /// Init actor methods available
 #[derive(FromPrimitive)]
+#[repr(u64)]
 pub enum Method {
     Constructor = METHOD_CONSTRUCTOR,
 }
@@ -19,7 +20,7 @@ pub enum Method {
 impl Method {
     /// Converts a method number into a Method enum
     fn from_method_num(m: MethodNum) -> Option<Method> {
-        FromPrimitive::from_u64(u64::from(m))
+        FromPrimitive::from_u64(m)
     }
 }
 
diff --git a/vm/actor/src/lib.rs b/vm/actor/src/lib.rs
index b54ee08d3272..da84aec8bee2 100644
--- a/vm/actor/src/lib.rs
+++ b/vm/actor/src/lib.rs
@@ -9,7 +9,7 @@ mod util;
 
 pub use self::builtin::*;
 pub use self::util::*;
-pub use vm::{ActorID, ActorState, DealID, Serialized};
+pub use vm::{ActorState, DealID, Serialized};
 
 use encoding::Error as EncodingError;
 use ipld_blockstore::BlockStore;
diff --git a/vm/src/actor_state.rs b/vm/src/actor_state.rs
index ef3dcacd2fbc..e90086a77b15 100644
--- a/vm/src/actor_state.rs
+++ b/vm/src/actor_state.rs
@@ -3,22 +3,11 @@
 
 use crate::TokenAmount;
 use cid::Cid;
-use encoding::Cbor;
 use num_bigint::biguint_ser::{BigUintDe, BigUintSer};
 use serde::{Deserialize, Deserializer, Serialize, Serializer};
-use std::ops::AddAssign;
 
 /// Identifier for Actors, includes builtin and initialized actors
-#[derive(PartialEq, Eq, Copy, Clone, Debug, Serialize, Deserialize, Default)]
-pub struct ActorID(pub u64);
-
-impl AddAssign<u64> for ActorID {
-    fn add_assign(&mut self, other: u64) {
-        self.0 += other
-    }
-}
-
-impl Cbor for ActorID {}
+pub type ActorID = u64;
 
 /// State of all actor implementations
 #[derive(PartialEq, Eq, Clone, Debug)]
diff --git a/vm/src/method.rs b/vm/src/method.rs
index 472604534e7b..34e93517fa3d 100644
--- a/vm/src/method.rs
+++ b/vm/src/method.rs
@@ -2,30 +2,15 @@
 // SPDX-License-Identifier: Apache-2.0, MIT
 
 use encoding::{de, from_slice, ser, serde_bytes, to_vec, Cbor, Error as EncodingError};
-use serde::{Deserialize, Serialize};
 use std::ops::Deref;
 
 /// Method number indicator for calling actor methods
-#[derive(Default, Clone, Copy, PartialEq, Debug, Serialize, Deserialize)]
-pub struct MethodNum(pub u64); // TODO: add constraints to this
-
-impl MethodNum {
-    /// Constructor for new MethodNum
-    pub fn new(num: u64) -> Self {
-        Self(num)
-    }
-}
-
-impl From<MethodNum> for u64 {
-    fn from(method_num: MethodNum) -> u64 {
-        method_num.0
-    }
-}
+pub type MethodNum = u64;
 
 /// Base actor send method
-pub const METHOD_SEND: isize = 0;
+pub const METHOD_SEND: MethodNum = 0;
 /// Base actor constructor method
-pub const METHOD_CONSTRUCTOR: isize = 1;
+pub const METHOD_CONSTRUCTOR: MethodNum = 1;
 
 /// Serialized bytes to be used as parameters into actor methods
 #[derive(Clone, PartialEq, Debug)]
diff --git a/vm/tests/params_test.rs b/vm/tests/params_test.rs
index 73868586fef8..0d6bf1a1145b 100644
--- a/vm/tests/params_test.rs
+++ b/vm/tests/params_test.rs
@@ -3,7 +3,7 @@
 
 use address::Address;
 use encoding::{from_slice, to_vec};
-use vm::{MethodNum, Serialized};
+use vm::Serialized;
 
 #[test]
 fn serialized_deserialize() {
@@ -38,10 +38,3 @@ fn cbor_params() {
     let params = Serialized::serialize(addr.clone()).unwrap();
     assert_eq!(from_slice::<Address>(&params).unwrap(), addr);
 }
-
-#[test]
-fn method_num() {
-    // Test constructor available publicly
-    let method = MethodNum::new(1);
-    assert_eq!(1 as u64, u64::from(method));
-}