diff --git a/ethers.nimble b/ethers.nimble
index ea548fa..48d8f72 100644
--- a/ethers.nimble
+++ b/ethers.nimble
@@ -7,6 +7,7 @@ requires "chronos >= 3.0.0 & < 4.0.0"
 requires "contractabi >= 0.4.0 & < 0.5.0"
 requires "questionable >= 0.10.2 & < 0.11.0"
 requires "json_rpc"
+requires "stint"
 requires "stew"
 
 task test, "Run the test suite":
diff --git a/ethers/basics.nim b/ethers/basics.nim
index 2390d31..ecad3e5 100644
--- a/ethers/basics.nim
+++ b/ethers/basics.nim
@@ -1,7 +1,9 @@
 import pkg/chronos
 import pkg/questionable
+import pkg/stint
 import ./address
 
 export chronos
 export address
 export questionable
+export stint
diff --git a/ethers/provider.nim b/ethers/provider.nim
index d9df3c6..78b83e5 100644
--- a/ethers/provider.nim
+++ b/ethers/provider.nim
@@ -1,2 +1,9 @@
+import ./basics
+
+export basics
+
 type
   Provider* = ref object of RootObj
+
+method getBlockNumber*(provider: Provider): Future[UInt256] {.base.} =
+  doAssert false, "not implemented"
diff --git a/ethers/providers/jsonrpc.nim b/ethers/providers/jsonrpc.nim
index 0a180d0..7822425 100644
--- a/ethers/providers/jsonrpc.nim
+++ b/ethers/providers/jsonrpc.nim
@@ -35,3 +35,7 @@ proc send*(provider: JsonRpcProvider,
 proc listAccounts*(provider: JsonRpcProvider): Future[seq[Address]] {.async.} =
   let client = await provider.client
   return await client.eth_accounts()
+
+method getBlockNumber*(provider: JsonRpcProvider): Future[UInt256] {.async.} =
+  let client = await provider.client
+  return await client.eth_blockNumber()
diff --git a/ethers/providers/rpccalls/conversions.nim b/ethers/providers/rpccalls/conversions.nim
index 0d75404..6f75b02 100644
--- a/ethers/providers/rpccalls/conversions.nim
+++ b/ethers/providers/rpccalls/conversions.nim
@@ -1,11 +1,21 @@
 import std/json
 import ../../basics
 
+# Address
+
 func `%`*(address: Address): JsonNode =
   %($address)
 
-func fromJson*(json: JsonNode, argname: string, result: var Address) =
+func fromJson*(json: JsonNode, name: string, result: var Address) =
   if address =? Address.init(json.getStr()):
     result = address
   else:
-    raise newException(ValueError, "\""  & argname & "\"is not an Address")
+    raise newException(ValueError, "\""  & name & "\"is not an Address")
+
+# UInt256
+
+func `%`*(integer: UInt256): JsonNode =
+  %toHex(integer)
+
+func fromJson*(json: JsonNode, name: string, result: var UInt256) =
+  result = UInt256.fromHex(json.getStr())
diff --git a/ethers/providers/rpccalls/signatures.nim b/ethers/providers/rpccalls/signatures.nim
index 892b68b..a439c3e 100644
--- a/ethers/providers/rpccalls/signatures.nim
+++ b/ethers/providers/rpccalls/signatures.nim
@@ -1 +1,2 @@
 proc eth_accounts: seq[Address]
+proc eth_blockNumber: UInt256
diff --git a/nim.cfg b/nim.cfg
index 8589cf1..7dce504 100644
--- a/nim.cfg
+++ b/nim.cfg
@@ -1 +1,2 @@
 -d:"chronicles_log_level=INFO"
+--warning[LockLevel]:off
diff --git a/testmodule/testJsonRpcProvider.nim b/testmodule/testJsonRpcProvider.nim
index afce486..10c41c4 100644
--- a/testmodule/testJsonRpcProvider.nim
+++ b/testmodule/testJsonRpcProvider.nim
@@ -26,3 +26,9 @@ suite "JsonRpcProvider":
   test "sends raw messages to the provider":
     let response = await provider.send("evm_mine")
     check response == %"0x0"
+
+  test "returns block number":
+    let blocknumber1 = await provider.getBlockNumber()
+    discard await provider.send("evm_mine")
+    let blocknumber2 = await provider.getBlockNumber()
+    check blocknumber2 > blocknumber1