Policy Rate vs. Real Rate: Why the TPM Has Nothing to Do with What You Pay

When Peru's central bank cut its policy rate to 4.25%, financial media celebrated. "Credit gets cheaper," read the headlines.

For small business operators, nothing changed. They still pay 20%.

The disconnect between monetary policy rates and what SMEs actually pay for credit is one of the most poorly understood dynamics in Latin American finance. This post traces the credit transmission mechanism from central bank to small business, quantifying the markup at each step.

The Transmission Chain

Credit doesn't flow directly from central banks to businesses. It passes through a series of intermediaries, each adding a margin:

Central Bank → Interbank Market → Wholesale Lending → Corporate Credit → PYME Credit → Fintech Credit → Informal Credit

Each hop adds 2-5 percentage points. By the time capital reaches a small operator, the policy rate is a distant memory.

Country-by-Country: The Broken Pipeline

Chile: 4.5% → 11% (6.5pp gap)

Chile has the most efficient credit transmission in LATAM, yet the gap is still significant:

• TPM (BCCh): 4.5%
• Interbank (TAB): ~5.0%
• Corporate credit: 6-8%
• PYME credit: 11%
• Fintech: 15-25%

Chile's relatively small gap reflects its developed banking sector and strong regulatory framework. Even here, a small operator pays 2.4x the policy rate.

Peru: 4.25% → 20% (15.75pp gap)

Peru has the most extreme disconnection in the region:

• BCRP reference rate: 4.25%
• Interbank: ~4.75%
• Corporate credit: 6-7%
• PYME credit (SBS data): 20-27%
• Microenterprise: 30-45%
• Informal: 25-60%

The SBS publishes granular data by enterprise size. The jump from corporate (7%) to small business (20%) happens within the same banks, for the same currency, in the same country. The spread is information asymmetry and underwriting cost, crystallized as interest rates.

Colombia: 11.25% → 21% (9.75pp gap)

Colombia's high policy rate amplifies the spread:

• BanRep reference rate: 11.25%
• Corporate credit: 13-14%
• PYME credit: 21%
• Usury cap: 24.4%
• Informal: 30-50%

Note: Colombia's usury cap (tasa de usura) at 24.4% creates a ceiling that compresses the formal PYME market, but pushes operators who can't qualify at 21% directly into the informal market at 30-50%.

Mexico: 9.5% → 16.5% (7pp gap)

Mexico's CAT (Costo Anual Total) reveals the true cost:

• Banxico reference rate: 9.5%
• Corporate credit: 9-10%
• PYME nominal rate: 14-16.5%
• PYME CAT (all-in cost): 17-35%
• Fintech (Konfio, etc.): 29-45%

The CAT, Mexico's all-inclusive cost metric, often runs 5-15pp above the nominal rate. When 89% of Mexican SMEs call bank access "very difficult," the CAT explains why.

Brazil: 14.75% → 24% (9.25pp gap)

Brazil starts from a high base and adds more:

• Selic rate: 14.75%
• Corporate credit: 16-18%
• PYME credit (OECD): 23.74%
• Small enterprise: 24-30%
• BNDES (subsidized): 10-14%, but reaches only ~2% of PYMEs

Brazil's BNDES offers the best rates in the region, but its reach is limited to larger, established companies. For the other 98% of SMEs, rates start at 24%.

Uruguay: 9% → 21% (12pp gap)

BCU data reveals one of the steepest markups:

• BCU reference rate: 9%
• Corporate credit: 12-13%
• PYME (mediana empresa): 21%
• PYME (pequena empresa): 30-37%
• Informal: 25-35%

Uruguay's small business rates are among the highest in the region relative to the policy rate. The BCU publishes exact rates by enterprise size, there is no ambiguity.

Why Lowering the TPM Doesn't Help

Central bank rate cuts are transmitted unevenly. Here's the typical pass-through:

When Peru's BCRP cuts 100 basis points, corporate borrowers see 60-80bps of relief. PYME borrowers see 10-30bps, if any. The structural intermediation costs (risk assessment, regulatory capital, collateral enforcement) are fixed costs that don't compress with lower policy rates.

The Hidden Cost: FX Risk

For operators in local-currency markets, there's an additional hidden cost: currency depreciation.

A loan denominated in Colombian pesos at 21% nominal carries an additional 3-4% annual cost from peso depreciation against USD. The "real" cost in dollar terms is often 24-25%.

Dollarized economies (Panama, Ecuador) don't have this problem. Neither do structures denominated in stable assets.

What This Means for Operators

Three practical implications:

Don't wait for rate cuts. If the central bank cuts 100bps, your PYME rate might drop 10-30bps. The macro environment has minimal impact on your cost of capital.

Compare against PYME rates, not policy rates. When evaluating any financing option, the benchmark isn't the TPM; it's what your bank would actually charge you (or whether they'd serve you at all).

Structure matters more than rate. The difference between a 20% amortizing loan and a 12% interest-only structure, over 5 years, is more impactful than any policy rate movement.

The Structural Solution

If the transmission mechanism is broken, and the data shows it clearly is, the fix isn't a better transmission mechanism. It's an alternative channel that connects capital directly to assets, bypassing the intermediation layers that add 7-16 percentage points.

This is why asset-based evaluation matters. It's not about "disrupting" banks. It's about serving the market the transmission mechanism structurally cannot reach.

Data sources: BCCh Chile (Tasas de Interes), BCRP Peru (Nota Semanal), BanRep Colombia (Informe de Tasas), Banxico Mexico (Indicadores Financieros), BCB Brazil (SGS), BCU Uruguay (Tasas Medias), OECD Financing SMEs Scoreboard 2024. FX depreciation estimates based on 5-year average COP/USD and BRL/USD movements.