diff --git a/test_libs/pyspec/eth2spec/test/helpers/deposits.py b/test_libs/pyspec/eth2spec/test/helpers/deposits.py
index ca8b23361..eea019e8b 100644
--- a/test_libs/pyspec/eth2spec/test/helpers/deposits.py
+++ b/test_libs/pyspec/eth2spec/test/helpers/deposits.py
@@ -60,7 +60,7 @@ def build_deposit(spec,
     return deposit, root, deposit_data_leaves
 
 
-def prepare_genesis_deposits(spec, genesis_validator_count, signed=False):
+def prepare_genesis_deposits(spec, genesis_validator_count, amount, signed=False):
     genesis_deposit_data_list = []
     deposit_data_leaves = []
     for validator_index in range(genesis_validator_count):
@@ -71,7 +71,7 @@ def prepare_genesis_deposits(spec, genesis_validator_count, signed=False):
         deposit_data = spec.DepositData(
             pubkey=pubkey,
             withdrawal_credentials=withdrawal_credentials,
-            amount=spec.MAX_EFFECTIVE_BALANCE,
+            amount=amount,
         )
         if signed:
             sign_deposit_data(spec, deposit_data, privkey)  # state=None
@@ -84,7 +84,7 @@ def prepare_genesis_deposits(spec, genesis_validator_count, signed=False):
 
     genesis_deposits = (
         spec.Deposit(proof=list(get_merkle_proof(tree, item_index=index)), data=deposit_data)
-        for index, deposit_data in enumerate(genesis_deposit_data_list) 
+        for index, deposit_data in enumerate(genesis_deposit_data_list)
     )
 
     return genesis_deposits, root
diff --git a/test_libs/pyspec/eth2spec/test/sanity/test_genesis.py b/test_libs/pyspec/eth2spec/test/sanity/test_genesis.py
index d6b3bf940..7e5fd5db4 100644
--- a/test_libs/pyspec/eth2spec/test/sanity/test_genesis.py
+++ b/test_libs/pyspec/eth2spec/test/sanity/test_genesis.py
@@ -8,7 +8,7 @@ from eth2spec.test.helpers.deposits import (
 @spec_state_test
 def test_is_genesis_trigger_false(spec, state):
     deposit_count = 2
-    genesis_deposits, deposit_root = prepare_genesis_deposits(spec, deposit_count)
+    genesis_deposits, deposit_root = prepare_genesis_deposits(spec, deposit_count, spec.MAX_EFFECTIVE_BALANCE)
     genesis_time = 1234
 
     is_triggered = spec.is_genesis_trigger(genesis_deposits, genesis_time, deposit_root)
@@ -21,7 +21,7 @@ def test_is_genesis_trigger_false(spec, state):
 @spec_state_test
 def test_is_genesis_trigger_true(spec, state):
     deposit_count = spec.GENESIS_ACTIVE_VALIDATOR_COUNT
-    genesis_deposits, deposit_root = prepare_genesis_deposits(spec, deposit_count)
+    genesis_deposits, deposit_root = prepare_genesis_deposits(spec, deposit_count, spec.MAX_EFFECTIVE_BALANCE)
     genesis_time = 1234
 
     is_triggered = spec.is_genesis_trigger(genesis_deposits, genesis_time, deposit_root)
@@ -29,12 +29,26 @@ def test_is_genesis_trigger_true(spec, state):
 
     yield is_triggered
 
+@with_phases(['phase0'])
+@spec_state_test
+def test_is_genesis_trigger_not_enough_balance(spec, state):
+    deposit_count = spec.GENESIS_ACTIVE_VALIDATOR_COUNT
+    genesis_deposits, deposit_root = prepare_genesis_deposits(spec, deposit_count, spec.MAX_EFFECTIVE_BALANCE - 1)
+    genesis_time = 1234
+    yield genesis_deposits
+    yield genesis_time
+
+    is_triggered = spec.is_genesis_trigger(genesis_deposits, genesis_time, deposit_root)
+    assert is_triggered is False
+
+    yield is_triggered
+
 
 @with_phases(['phase0'])
 @spec_state_test
 def test_genesis(spec, state):
     deposit_count = spec.GENESIS_ACTIVE_VALIDATOR_COUNT
-    genesis_deposits, deposit_root = prepare_genesis_deposits(spec, deposit_count)
+    genesis_deposits, deposit_root = prepare_genesis_deposits(spec, deposit_count, spec.MAX_EFFECTIVE_BALANCE)
     genesis_time = 1234
 
     yield genesis_deposits