diff --git a/openbb_terminal/fixedincome/ecb_view.py b/openbb_terminal/fixedincome/ecb_view.py
index c169c5a061c..9840ad3ea4c 100644
--- a/openbb_terminal/fixedincome/ecb_view.py
+++ b/openbb_terminal/fixedincome/ecb_view.py
@@ -72,7 +72,7 @@ def plot_estr(
     external_axes: Optional[List[plt.Axes]]
         External axes (1 axis is expected in the list)
     """
-    series_id = ESTR_PARAMETER_TO_ECB_ID.get(series_id)
+    series_id = ESTR_PARAMETER_TO_ECB_ID.get(series_id, "")
 
     df = ecb_model.get_series_data(
         series_id, start_date if start_date else "", end_date if end_date else ""
diff --git a/openbb_terminal/fixedincome/econdb_model.py b/openbb_terminal/fixedincome/econdb_model.py
index ffb3c384329..f79105d94b9 100644
--- a/openbb_terminal/fixedincome/econdb_model.py
+++ b/openbb_terminal/fixedincome/econdb_model.py
@@ -69,8 +69,8 @@ TREASURIES: Dict = {
 
 @log_start_end(log=logger)
 def get_treasuries(
-    instruments: list = None,
-    maturities: list = None,
+    instruments: Optional[list] = None,
+    maturities: Optional[list] = None,
     frequency: str = "monthly",
     start_date: str = "1900-01-01",
     end_date: Optional[str] = None,
diff --git a/openbb_terminal/fixedincome/fixedincome_controller.py b/openbb_terminal/fixedincome/fixedincome_controller.py
index 8bae475a02d..9a4a5f34860 100644
--- a/openbb_terminal/fixedincome/fixedincome_controller.py
+++ b/openbb_terminal/fixedincome/fixedincome_controller.py
@@ -5,7 +5,7 @@ __docformat__ = "numpy"
 
 import argparse
 import logging
-from typing import List
+from typing import List, Optional
 
 import pandas as pd
 
@@ -58,7 +58,7 @@ class FixedIncomeController(BaseController):
     PATH = "/fixedincome/"
     CHOICES_GENERATION = True
 
-    def __init__(self, queue: List[str] = None):
+    def __init__(self, queue: Optional[List[str]] = None):
         """Constructor"""
         super().__init__(queue)
 
diff --git a/openbb_terminal/fixedincome/fred_model.py b/openbb_terminal/fixedincome/fred_model.py
index af4717e89ce..df15570f42d 100644
--- a/openbb_terminal/fixedincome/fred_model.py
+++ b/openbb_terminal/fixedincome/fred_model.py
@@ -109,7 +109,7 @@ def get_yield_curve(
     date: str = "",
     return_date: bool = False,
     inflation_adjusted: bool = False,
-    spot_or_par: str = None,
+    spot_or_par: Optional[str] = None,
 ) -> Tuple[pd.DataFrame, str]:
     """Gets yield curve data from FRED.
 
@@ -185,7 +185,7 @@ def get_yield_curve(
         years = YIELD_CURVE_REAL_RATES
     elif spot_or_par:
         if spot_or_par == "spot":
-            years = YIELD_CURVE_SPOT_RATES
+            years = YIELD_CURVE_SPOT_RATES  # type: ignore
             fred_series = YIELD_CURVE_SERIES_CORPORATE_SPOT
         elif spot_or_par == "par":
             years = YIELD_CURVE_PAR_RATES
@@ -194,7 +194,7 @@ def get_yield_curve(
             console.print("Please select either 'spot' or 'par' rates.")
     else:
         fred_series = YIELD_CURVE_SERIES_NOMINAL
-        years = YIELD_CURVE_NOMINAL_RATES
+        years = YIELD_CURVE_NOMINAL_RATES  # type: ignore
 
     for key, s_id in fred_series.items():
         df = pd.concat(
diff --git a/openbb_terminal/fixedincome/fred_view.py b/openbb_terminal/fixedincome/fred_view.py
index 2247a94e476..4aff8ec12ff 100644
--- a/openbb_terminal/fixedincome/fred_view.py
+++ b/openbb_terminal/fixedincome/fred_view.py
@@ -5,7 +5,7 @@ import logging
 import os
 import pathlib
 from itertools import cycle
-from typing import List, Optional
+from typing import Dict, List, Optional
 
 import pandas as pd
 from matplotlib import pyplot as plt
@@ -179,7 +179,7 @@ ICE_BOFA_TO_OPTIONS = {
     ],
 }
 
-MOODY_TO_OPTIONS = {
+MOODY_TO_OPTIONS: Dict[str, Dict] = {
     "Type": {
         "aaa": {
             "index": {
@@ -212,7 +212,7 @@ MOODY_TO_OPTIONS = {
             },
         },
     },
-    "Spread": ["treasury", "fed_funds"],
+    "Spread": ["treasury", "fed_funds"],  # type: ignore
 }
 
 CP_TO_OPTIONS = {
@@ -1997,7 +1997,7 @@ def plot_icebofa(
 @check_api_key(["API_FRED_KEY"])
 def plot_moody(
     data_type: str = "aaa",
-    spread: str = None,
+    spread: Optional[str] = None,
     start_date: Optional[str] = None,
     end_date: Optional[str] = None,
     raw: bool = False,
diff --git a/openbb_terminal/fixedincome/oecd_model.py b/openbb_terminal/fixedincome/oecd_model.py
index 1947abc19f5..a9980389a17 100644
--- a/openbb_terminal/fixedincome/oecd_model.py
+++ b/openbb_terminal/fixedincome/oecd_model.py
@@ -3,6 +3,7 @@ __docformat__ = "numpy"
 
 import logging
 from datetime import datetime
+from typing import List, Optional
 
 import pandas as pd
 
@@ -64,7 +65,7 @@ COUNTRY_TO_CODE = {
 @log_start_end(log=logger)
 def get_interest_rate_data(
     data: str = "short",
-    countries: list = None,
+    countries: Optional[List[str]] = None,
     start_date: str = "",
     end_date: str = "",
 ) -> pd.DataFrame:
@@ -174,7 +175,7 @@ def get_interest_rate_data(
     df = df.iloc[:, [0, 5]]
 
     result = pd.DataFrame()
-    for country in countries:
+    for country in countries:  # type: ignore
         temp = pd.DataFrame(df[df["LOCATION"] == COUNTRY_TO_CODE[country]]["Value"])
         temp.columns = [f"{country} ({data_name})"]
         result = pd.concat([result, temp], axis=1)
diff --git a/openbb_terminal/fixedincome/oecd_view.py b/openbb_terminal/fixedincome/oecd_view.py
index dc2567f238a..a1301ad61aa 100644
--- a/openbb_terminal/fixedincome/oecd_view.py
+++ b/openbb_terminal/fixedincome/oecd_view.py
@@ -26,8 +26,8 @@ logger = logging.getLogger(__name__)
 
 @log_start_end(log=logger)
 def plot_treasuries(
-    short_term: list = None,
-    long_term: list = None,
+    short_term: Optional[list] = None,
+    long_term: Optional[list] = None,
     forecast: bool = False,
     start_date: Optional[str] = None,
     end_date: Optional[str] = None,