IMF Study Finds Monetary Policy in Africa Still Weak Despite Banking Sector Gains

A new study by the International Monetary Fund (IMF) has found that central banks across Sub-Saharan Africa are becoming more effective at using interest rates to control inflation and influence economic activity. However, the overall impact of monetary policy in the region remains much weaker than in advanced economies because of shallow financial markets, weak institutions and heavy fiscal pressures.

The IMF working paper, authored by Johanna Tiedemann, Olivier Bizimana and Kiswendsida Tougouma, examines 11 emerging and frontier economies in Sub-Saharan Africa between 2002 and 2023, including Ghana, Kenya, Nigeria, South Africa, Uganda and regional blocs such as WAEMU and CEMAC.

Banks Remain the Main Transmission Channel

The study finds that commercial banks play the biggest role in transmitting monetary policy across the region. When central banks raise policy rates, borrowing costs for businesses and households also rise, especially in countries with relatively stronger financial systems.

South Africa, Ghana, Mozambique and Uganda showed the clearest and strongest responses. In these economies, lending rates increased significantly after monetary tightening, showing that policy decisions are reaching the banking system.

Researchers noted that African economies still rely heavily on banks because capital markets remain underdeveloped. This makes the bank lending channel far more important than stock markets or bond markets in shaping economic activity.

At the same time, the study found that financial transmission remains uneven. In several countries, money market responses were weak or short-lived, suggesting that some central banks still struggle to fully influence market interest rates.

Exchange Rates Often Move in the Wrong Direction

One of the most surprising findings in the report concerns exchange rates. In theory, higher interest rates should strengthen a country’s currency by attracting investors seeking better returns. But in many African economies, currencies actually weakened after interest rate hikes.

The IMF researchers found that currencies in Nigeria, Zambia, South Africa and Ghana often depreciated following monetary tightening. Kenya was one of the few countries where the exchange rate reacted in the expected direction.

The report says this “exchange rate puzzle” reflects structural problems in many African economies. Foreign exchange markets are shallow, global financial integration remains limited and several governments continue to manage exchange rates directly or indirectly.

Because of these conditions, higher interest rates alone are often not enough to stabilize currencies or attract strong capital inflows.

Inflation and Growth Respond Slowly

The study also shows that monetary policy has only modest effects on inflation and economic growth compared with advanced economies.

According to the findings, a 100-basis-point increase in policy rates reduces real GDP in Sub-Saharan African frontier and emerging economies by about 0.2 percent at peak impact. Inflation falls gradually and often only after two years.

In advanced economies, the impact is far stronger and faster.

Researchers say this weak response reflects structural limitations such as underdeveloped financial systems, limited financial inclusion, weak monetary policy frameworks and fiscal dominance. In many countries, governments borrow heavily from domestic financial systems, limiting central banks’ ability to tighten policy aggressively.

The report also found that countries using inflation-targeting frameworks, including South Africa, Ghana, Kenya and Uganda, generally experienced stronger and more predictable monetary policy transmission than countries relying on monetary aggregates or mixed policy systems.

Transparency and Financial Development Matter Most

The IMF study highlights financial development and monetary policy transparency as two of the biggest factors shaping policy effectiveness across Africa.

Countries with more developed banking systems and stronger financial markets showed stronger responses to monetary tightening. Similarly, central banks that clearly communicated policy goals and decisions achieved better transmission outcomes.

The researchers argue that transparency helps households, investors and businesses better understand central bank actions, making monetary policy more credible and effective.

Fiscal discipline also mattered. Economies with lower fiscal dominance, where governments rely less on central bank financing, generally showed stronger monetary policy transmission.

Africa’s Central Banks Are Improving, But Challenges Remain

Overall, the IMF concludes that monetary policy in Sub-Saharan Africa is improving but remains constrained by structural weaknesses.

Central banks are increasingly able to influence financial conditions, especially through the banking system, but their ability to control inflation, stabilize exchange rates and manage economic cycles remains limited compared with more advanced economies.

The report says stronger institutions, deeper financial markets, better policy communication and lower fiscal pressures will be essential if African central banks are to make monetary policy more effective in the years ahead.