Fixed Income Investing: Everything You Need to Know

July 28, 2026

Protecting capital is a concern for many savers, and investing in fixed income effectively addresses this issue. By adding it to your financial strategies, you not only gain predictable returns but also shield your portfolio against unforeseen market volatility.

What is fixed income?

Both the public sector and private companies require financing and, to obtain it, they issue debt assets. This set of instruments is what we know as investing in fixed income.

In exchange for your capital, the organization commits to returning the funds on the agreed-upon date and paying interest or coupons. Unlike equities, this market offers complete certainty, as you know the exact return in advance.

¿Cuánto ganarías si inviertes desde hoy? Descúbrelo aquí.

Why invest in fixed income?

This financial market offers compelling arguments for those who prioritize stability.

Capital preservation

Conservative profiles prioritize the security of their savings over extraordinary returns. The issuer's repayment obligation offers superior protection compared to equities.

Recurring income

Private investors and pension funds require constant cash flows to cover their expenses. Quarterly, semi-annual, or annual coupon payments ensure predictable liquidity.

Portfolio diversification

Equities and debt often move in opposite directions when the economy falters. Therefore, including these securities in your strategy acts as a shield against stock market downturns.

Key characteristics

The following factors determine the behavior, security, and final yield of each security.

Issuer of the security

The type of entity requesting the funds determines the debt structure, the level of security, and the asset's yield.

Public sector

When you purchase government debt, you are financing the country's development and its budget. In return, you receive one of the safest investments on the market, as the entire state tax collection system backs your investment.

Private sector

Corporations turn to this market to fund their expansion plans, mergers, or operational needs. Since they lack the backing of a state, these securities carry a higher credit risk.

Maturity date

The instrument's time horizon directly influences its liquidity and exposure to interest rate fluctuations.

Short term

Assets with a maturity of less than eighteen months offer high liquidity and minimal risk. Their prices remain stable, making them ideal for short-term capital growth. 

Long term

Securities with maturities of five, ten, or thirty years require a long-term commitment of capital. In exchange for this time commitment, investors demand significantly higher annual returns.

Yield and coupons

The method by which an asset calculates and distributes earnings defines the remuneration strategy for the security holder.

Fixed coupon

The issuer pays a constant percentage throughout the life of the asset. Consequently, you receive the exact same amount at each maturity date, regardless of changes in the broader economy.

Floating or variable coupon

Interest payments are linked to a benchmark index such as the Euribor plus a fixed spread. Consequently, the return fluctuates periodically in line with increases or decreases in official interest rates. 

Types of fixed-income securities

The market offers a wide range of financial instruments tailored to the needs of each investor profile when investing in fixed income.

Treasury Bills

The State issues these short-term assets with maturities of 3, 6, 9, and 12 months. The Treasury uses a discount system, where the investor acquires them at a price lower than the final nominal value.

Government Bonds

These form the basis of medium-term public financing, with maturities between 2 and 5 years. They pay explicit annual coupons, and their yield serves as a barometer for the country's financial health.

Government Obligations

They share the same technical characteristics as bonds but are geared toward the long term with a terms of 10, 15, 30 years or more. The Spanish Treasury regularly auctions these assets to institutional and retail investors.

Corporate promissory notes

This is short-term corporate debt issued by large private companies. They function similarly to Treasury bills, as they are sold at a discount to meet financing needs.

Corporate bonds

These are private debt securities issued by companies for the medium and long term to finance investments, paying fixed or variable coupons depending on the market.

Subordinated debt

These private assets offer higher returns because they carry subordination risk: in the event of bankruptcy, holders are paid after ordinary creditors.

¿Cuánto ganarías si inviertes desde hoy? Descúbrelo aquí.

Other types of fixed income

The financial market offers other alternatives for fixed income investment to meet specific needs:

  • Preferred shares. Perpetual securities without voting rights; coupon payments are contingent upon the company generating distributable profits.
  •   Convertible bonds. Hybrid assets that grant the right to exchange debt for company shares at predetermined prices and dates.
  • Green and social bonds. Instruments dedicated exclusively to projects with a positive environmental impact or social improvements.

These instruments demonstrate the versatility of the debt market. Evaluating their specific terms allows you to leverage their advantages in line with global economic trends.

How to invest in fixed income: a step-by-step guide

The process of incorporating these assets into a financial portfolio requires structured planning. First, set your goals and deadlines: determine whether you are saving to purchase a home in the near term or to secure your long-term retirement.

Second, open a securities account with a bank, a regulated broker, or directly through the central bank. Always compare purchase, custody, and collection fees, as these costs reduce your net return.

Finally, analyze the ratings from rating agencies to select the best securities. Once chosen, execute the purchase in the corresponding market and begin earning a return on your money.

Fixed-income taxation

In Spain, fixed-income returns are taxed as savings income under personal income tax as investment income on a progressive scale. Gains are taxed at 19% up to 6,000 euros and 21% between 6,000 and 50,000 euros.

Subsequently, the rates applied are: 23% up to 200,000 euros, 27% up to 300,000 euros, and 28% on amounts exceeding that. Financial institutions automatically withhold the percentage when paying each coupon.

Fixed income vs. variable income

The main distinction lies in the certainty and risk. When investing in fixed income, the economic rights of the contract are established from the outset. In contrast, variable income is uncertain regarding dividends and market prices; stocks have no maturity date and carry the risk of total loss.

Conversely, bonds guarantee absolute priority of payment over shareholders, although they cap returns at the agreed-upon coupon. Furthermore, their lower volatility provides peace of mind during recessions or crises.

Benefits of fixed income

This market provides financial visibility and facilitates wealth management, both for families and corporations. Contracts require the issuer to be held accountable for delays, while the secondary market allows for the sale of securities in advance to obtain immediate liquidity.

Limitations and risks

Although these assets provide stability, the debt market can also impact returns. Evaluating the following risks will help you protect your capital.

Interest rates

When official interest rates rise, older bonds become less attractive and its price falls on the secondary market. This results in actual losses if you sell the securities before maturity.

Credit or default risk

This occurs when the issuer experiences solvency issues and fails to pay coupons or the principal. Rating agencies constantly assess this risk using qualitative ratings.

Inflation

If inflation exceeds the bond's nominal yield, you lose purchasing power. Even if you receive the interest and principal at maturity, your money will buy fewer goods and services than it did initially.

Recommendations before investing

Consider the following tips to maximize net returns when investing in fixed income.

  • Review reports from Moody's, S&P, or Fitch.
  • Combine government and corporate debt from various countries and sectors.
  • Hold securities until maturity if interest rates rise.
  • Deduct commissions and taxes from the transaction.

Apply these criteria transforms investment into an efficient activity. This discipline protects your capital against fluctuations in the financial environment.

FAQs

Can I lose money when investing in fixed income?

Yes. It is possible to incur losses if you sell the security early during a period of rising interest rates or if the issuer defaults on its payments.

What is the safest fixed-income investment?

Treasury bills and short-term government bonds from solvent countries are the safest options due to the backing of their sovereign governments.

¿Cuánto ganarías si inviertes desde hoy? Descúbrelo aquí.

Conclusion

Knowing how to invest in fixed income is essential, but modern finance offers new alternatives. Domoblock is revolutionizing the sector through real estate tokenization, allowing you to invest in real estate with minimal capital.

Our technology platform simplifies the diversification of your portfolioMeet our team at Domoblock, explore your investment opportunities, and start earning returns on your savings today.

Sergio Navarro

Expert in blockchain, investments, and personal finance

Share on your social media

Do you like what you're reading?

Subscribe to our Newsletter

Do you like what you're reading?

Subscribe to our newsletter!

En curso

Madrid | Tres cantos

Calera, 3

DOMO-TCA-1
Flipping building

Funded

100%

598.506,15 €

Target

598.506,15 €

Rentabilidad estimada:
14,03%
Duración estimada
8 meses
Chat with other investors and ask your questions in our Telegram group

Related articles