The CDI (Certificado de Depósito Interbancário) is Brazil's primary interbank deposit rate, used by banks to lend money to each other overnight. It closely tracks the SELIC rate (the Brazilian central bank's overnight policy rate) and serves as the benchmark for nearly all fixed income investments in Brazil. Most Brazilian fixed income products — CDB (Certificate of Bank Deposit), LCI (Real Estate Credit Notes), LCA (Agribusiness Credit Notes), LCIs, and RDBs — are quoted as a percentage of the CDI rather than a fixed interest rate. For example, a CDB at 100% CDI will yield approximately the CDI rate; a CDB at 120% CDI yields 20% more than CDI. The CDI has historically been high in Brazil — in mid-2024 it was approximately 10.4% annually — reflecting Brazil's structurally higher interest rate environment compared to developed economies. Income tax on fixed income returns in Brazil uses a regressive table: 22.5% on gains from investments held up to 180 days, 20% from 181 to 360 days, 17.5% from 361 to 720 days, and 15% on gains held for more than 720 days. IOF (Imposto sobre Operações Financeiras) — a financial transactions tax — applies on early withdrawals within the first 30 days at rates declining from 96% on day 1 to 0% from day 30. LCI and LCA investments are exempt from income tax for individual investors, making them particularly attractive at equivalent or lower CDI percentages. CDBs are the standard taxable benchmark; LCI/LCAs at 80% CDI can be financially equivalent to a CDB at 97% CDI after considering the tax exemption.
Gross Return = Principal × CDI Rate × (CDI Percentage / 100) × Days / 360; Net Return (taxable) = Gross Return × (1 - IR Rate); Effective Comparable Rate: LCI/LCA Rate × 100% = CDB Taxable Rate × (1 - IR Rate); CDI to SELIC ratio ≈ 99.8-100%
- 1Identify the investment product: CDB (taxable), LCI (exempt), or LCA (exempt) and the CDI percentage offered.
- 2Check the current CDI rate published daily by CETIP/B3.
- 3Calculate the gross return: principal × CDI rate × percentage of CDI × holding period in days / 360.
- 4For taxable products (CDB), apply the applicable IR rate based on holding period (22.5%, 20%, 17.5%, or 15%).
- 5For LCI/LCA, the full gross return is retained with no income tax.
- 6Check for IOF on withdrawals within the first 30 days — avoid early redemption of fixed income investments.
- 7Compare LCI/LCA versus CDB using the equivalent yield formula to determine which offers the better after-tax return.
Held 361-720 days = 17.5% IR rate; IR withheld at source by the bank
R$50,000 × 10.4% = R$5,200 gross. IR at 17.5% = R$910. Net = R$5,200 - R$910 = R$4,290. Net yield = 8.58%.
LCI is IR-exempt; 88% CDI tax-free = better than 100% CDI after 17.5% tax
LCI: R$50K × 10.4% × 88% = R$4,576 net (no tax). CDB 100% net: R$4,290. LCI wins by R$286.
IOF plus IR on short-term redemptions makes early exits very costly
IOF = R$100 × 50% = R$50. After IOF: R$50 gain. IR 22.5% on R$50 = R$11.25. Net = R$50 - R$11.25 = R$38.75.
Any LCI above 85% CDI beats a CDB at 100% CDI held for 2+ years
CDB net = 100% × (1-15%) = 85% CDI equivalent. LCI at 85% CDI = same net. LCI at 87% CDI = better.
An investor comparing a CDB at 105% CDI versus an LCI at 90% CDI to determine which offers the better after-tax return for a 12-month horizon.. This application is commonly used by professionals who need precise quantitative analysis to support decision-making, budgeting, and strategic planning in their respective fields
A financial adviser explaining to a client why LCI/LCA should always be considered before CDB when the rates are comparable.. Industry practitioners rely on this calculation to benchmark performance, compare alternatives, and ensure compliance with established standards and regulatory requirements
A retiree calculating the monthly income from R$500,000 invested at 100% CDI after income tax, to plan living expenses.. Academic researchers and students use this computation to validate theoretical models, complete coursework assignments, and develop deeper understanding of the underlying mathematical principles
A university student deciding between a daily liquidity CDB (85% CDI) and a 6-month CDB (105% CDI) for an emergency fund.. Financial analysts and planners incorporate this calculation into their workflow to produce accurate forecasts, evaluate risk scenarios, and present data-driven recommendations to stakeholders
An accountant calculating the IR withholding on a client's annual CDB redemptions for the IRPF declaration.. This application is commonly used by professionals who need precise quantitative analysis to support decision-making, budgeting, and strategic planning in their respective fields
CDB with Liquidity (Liquidez Diária)
{'title': 'CDB with Liquidity (Liquidez Diária)', 'body': 'Some CDBs offer daily liquidity (resgate diário), allowing redemption at any time. However, these typically offer lower CDI percentages (80-95%) compared to locked-in CDBs (95-115%). The trade-off between liquidity and higher rates is a key investment decision, particularly for emergency fund allocation.'} When encountering this scenario in brazil cdi return calc calculations, users should verify that their input values fall within the expected range for the formula to produce meaningful results. Out-of-range inputs can lead to mathematically valid but practically meaningless outputs that do not reflect real-world conditions.
Tesouro Direto vs CDB
{'title': 'Tesouro Direto vs CDB', 'body': 'Tesouro Direto is the Brazilian government bond platform available to retail investors. Tesouro SELIC bonds function similarly to CDB at 100% SELIC/CDI but are issued by the federal government (zero credit risk). Tesouro Direto is subject to the same IR regressive table as CDB but has no FGC limit — it is backed by the government itself.'}
Prefixado (Pre-Fixed) Investments
{'title': 'Prefixado (Pre-Fixed) Investments', 'body': 'Instead of CDI-linked (post-fixed) investments, investors can choose pre-fixed instruments where the annual return is locked in at the time of purchase. Pre-fixed CDBs protect against CDI rate cuts but underperform if CDI rises. The decision between post-fixed and pre-fixed depends on interest rate expectations.'}
Indexado ao IPCA
{'title': 'Indexado ao IPCA', 'body': 'IPCA-indexed instruments (Tesouro IPCA+, CDB IPCA+) pay a fixed premium above the official inflation index. These protect against inflation and are suitable for long-term goals. Like other fixed income products, they are subject to the same IR regressive table based on holding period.'} When encountering this scenario in brazil cdi return calc calculations, users should verify that their input values fall within the expected range for the formula to produce meaningful results. Out-of-range inputs can lead to mathematically valid but practically meaningless outputs that do not reflect real-world conditions.
| Holding Period | IR Rate | Example: 10.4% CDI Gross | Net Yield |
|---|---|---|---|
| Up to 180 days | 22.5% | R$10,400 gross on R$100K | R$8,060 net = 8.06% |
| 181 to 360 days | 20.0% | R$10,400 gross on R$100K | R$8,320 net = 8.32% |
| 361 to 720 days | 17.5% | R$10,400 gross on R$100K | R$8,580 net = 8.58% |
| Above 720 days | 15.0% | R$10,400 gross on R$100K | R$8,840 net = 8.84% |
| LCI/LCA (any period) | 0% exempt | R$10,400 gross on R$100K | R$10,400 net = 10.40% |
What is the CDI rate and where can I find it?
The CDI is an overnight interbank rate published daily by B3 (formerly CETIP). It closely tracks the SELIC rate set by the Copom (Banco Central's Monetary Policy Committee). The CDI can be found on the B3 website, major investment platforms, or financial news portals. In mid-2024, it was approximately 10.4% annually.
What is the difference between CDB and LCI/LCA?
A CDB (Certificado de Depósito Bancário) is a bank deposit certificate — it is taxable, with IR applied at source based on holding period. LCIs (Letras de Crédito Imobiliário) and LCAs (Letras de Crédito do Agronegócio) are credit instruments backing real estate or agribusiness sectors — they are exempt from IR for individual investors, making them more attractive at equivalent rates.
Is my investment protected if the bank fails?
CDB, LCI, and LCA investments up to R$250,000 per CPF per institution are protected by FGC (Fundo Garantidor de Créditos) — Brazil's deposit insurance equivalent. This covers up to R$1 million per CPF across all FGC-protected institutions within a 4-year period. This protection makes bank fixed income products very safe for amounts within the limit.
What is IOF and how does it work?
IOF (Imposto sobre Operações Financeiras) is a tax on financial transactions including early redemption of fixed income investments within the first 30 days. The IOF rate decreases each day from 96% on day 1 to 0% from day 30 onwards. After 30 days, no IOF applies. IOF applies on the gross gain before income tax.
What is the 'come-cotas' and does it apply to CDI investments?
Come-cotas is a semi-annual tax collection mechanism applied to fixed income funds (FIFs) in May and November, at 15% or 20% on accrued gains. Direct CDB, LCI, and LCA investments are NOT subject to come-cotas — tax is only collected at redemption. Funds investing in these instruments (not the direct products) may be subject to come-cotas.
Are CDB returns declared in the IRPF?
IR on CDB returns is withheld at source by the bank — the investor receives the net amount automatically. The CDB investment and returns must still be declared in the annual IRPF in the 'Rendimentos Sujeitos à Tributação Exclusiva' section. Since IR is already withheld, no additional tax is owed at the annual return.
What happens to CDI investments if the SELIC rate falls?
CDI closely follows SELIC. If the Copom cuts the SELIC rate, CDI falls accordingly, reducing the return on CDI-linked investments from that point forward. Post-fixed CDI investments adjust dynamically — they earn the current CDI rate each day. Pre-fixed CDB investments at a locked rate are not affected by subsequent SELIC changes.
Can foreigners invest in CDI-linked products in Brazil?
Non-resident foreigners can invest in Brazilian fixed income through specific regulated channels (Resolução 4,373 or foreign direct investment accounts). Income remitted abroad is subject to withholding tax. The rules are complex and require a local custodian or bank to facilitate the investment. This is an important consideration when working with brazil cdi return calc calculations in practical applications. The answer depends on the specific input values and the context in which the calculation is being applied.
Pro Tip
For holding periods above 2 years, the IR rate drops to 15%. Combine this with LCI/LCA tax exemption knowledge to always calculate the after-IR equivalent rate before comparing any two fixed income products. The product with the highest after-tax net yield for your expected holding period is always the correct choice.
Did you know?
Brazil has had some of the world's highest real interest rates for decades. The SELIC rate peaked at 26.5% in 2003, and as recently as 2022-2024 was between 10-13.75%. This high rate environment makes Brazilian fixed income uniquely attractive by global standards — while European investors earn near-zero on savings, Brazilians earn double-digit returns on government-guaranteed instruments.