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CIA. DE SANEAMENTO BÁSICO DO ESTADO DE SÃO PAULO - SABESP

Rui de Britto Álvares Affonso

Chief Financial Officer and Investor Relations Officer

Mario Azevedo de Arruda Sampaio

Head of Capital Markets and Investor Relations

SABESP announces 2020 results São Paulo, March 25, 2021 - Companhia de Saneamento Básico do Estado de São Paulo - SABESP (B3: SBSP3; NYSE: SBS), one of the largest water and sewage services providers in the world based on the number of customers, announces today its fourth quarter and 2020 results. The Company’s operating and financial information, except when indicated otherwise is presented in Brazilian Reais, in accordance with the Brazilian Corporate Law. All comparisons in this release, unless otherwise stated, refer to the same period of 2019.

In 2020, the Company recorded net income of R$ 973.3 million, compared to net income of R$ 3,367.5 million in 2019, a decrease of R$ 2,394.2 million.

Adjusted EBITDA totaled R$ 6,421.8 million, down by R$ 1,088.7 million from the R$ 7,510.5 million reported in 2019.

The main factors were:

In June 2020, the Company entered into an agreement with the municipality of Mauá, starting operations in November. The impact of this agreement led to an increase of R$ 204.1 million in the 2020 operating revenue and a reversal of R$ 89.6 million in expenses, as shown below:

The economic instability worsened by COVID-19 impacted the Company, mainly with the:

The Company adopted the following measures during 2020, aiming to reduce exchange exposure:

As a result of these actions, the dollar-denominated debt fell by 84.1%, from US$ 1,051.9 million on December 31, 2019 to US$ 167.5 million on December 31, 2020.

Debt denominated in foreign currency accounted for 21% of total debt in 2020 (48% in 2019).

The operation in the municipality of Santo André, started in August 2019, represented a decrease of R$ 1,070.4 million in gross operating revenues and an increase of R$ 149.7 million in expenses year on year in 2020. The variation was due to the non-recurring accounting effects of the agreement entered into with the municipality. The operation in the municipality led to a positive result in 2020, as shown in the following table:

On February 20, 2009, Sabesp and the Public Prosecution Office of the State of São Paulo signed a Conduct Adjustment Term (TAC), in which the Company pledged to carry out the gradual dismissal of retired employees. As a result of this TAC, a provision was made for the dismissal of these employees.

The Public Prosecution Office closed the case regarding the TAC on October 11, 2019, given its understanding that the legal requirements were fully achieved. Accordingly, in 3Q19, R$ 173.3 million was reversed in expenses with Salaries, Payroll charges and Pension plan obligations as a non-recurring, the net effect in 2019 was a reversal of R$ 130.3 million.

In 2019, the Company signed program contracts with the municipalities of São Bernardo do Campo and Guarujá for 40 and 30 years, respectively. As a result, the Company ended all legal proceedings, which were recorded as non-recurring expenses, in the amounts of R$ 39.0 million and R$ 46.4 million, respectively.

In August 2019, a new health plan administered by Fundação CESP became effective, replacing the previous health plan, administered by SABESPREV.

Health care expenses were R$ 92.6 million lower in 2020. There was no need to make contributions this year, compared to the R$ 108.6 million recorded in 2019.

* Total shares = 683,509,869

Adjusted EBITDA Reconciliation (Non-accounting measures)

* Adjusted EBIT corresponds to net income before: (i) other operating revenues (expenses), net; (ii) financial result; and (iii) income tax and social contribution.

** Adjusted EBITDA corresponds to net income before: (i) other operating revenues (expenses), net; (ii) financial result; (iii) income tax and social contribution; and (iv) depreciation and amortization expenses.

In 2020, net operating revenue, which considers construction revenue, totaled R$ 17,797.5 million, down 1.0% from 2019.

Costs and expenses, which consider construction costs, totaled R$ 13,426.9 million, up 9.5% over 2019.

Adjusted EBIT totaled R$ 4,384.7 million, down 23.5% from the R$ 5,730.3 million recorded in 2019.

Adjusted EBITDA totaled R$ 6,421.8 million, down 14.5% from the R$ 7,510.5 million recorded in 2019.

The adjusted EBITDA margin reached 36.1% in 2020, compared to 41.8% in 2019.

Excluding the effects of revenues and construction costs, adjusted EBITDA margin reached 45.0% in 2020, compared to 49.5% in 2019.

The Company recorded net income of R$ 973.3 million in 2020, compared to net income of R$ 3,367.5 million in 2019.

The gross operating revenue related to the sanitation services, in the amount of R$ 15,157.8 million, which does not consider construction revenue, decreased by R$ 976.2 million or 6.1%, when compared to R$ 16,134.0 million in 2019.

The main factors that led to this decrease were:

The decrease in operating revenue was offset by:

In 2020, construction revenue increased by R$ 770.1 million, or 26.1%, compared to 2019. The variation was mainly due to higher asset investments.

The following tables show the water and sewage billed volume, on a quarter-over-quarter and year-over-year basis, per customer category and region. The volumes of Santo André, Mauá and the categories exempt from payment are presented individually.

Costs, administrative and selling expenses and construction costs increased by R$ 1,169.9 million in 2020 (9.5%). Excluding construction costs, the increase was R$ 421.2 million (4.5%).

Costs, administrative and selling expenses and construction costs as a percentage of net revenue was 75.4% in 2020, compared to 68.2% in 2019.

Salaries and Payroll charges and Pension plan obligations

In 2020, the R$ 34.9 million decrease was due to:

The above-mentioned decreases were mitigated by the reversal of R$ 130.3 million in expenses with TAC-Retirees in 2019, recorded as a non-recurring event.

Treatment supplies

Increase of R$ 28.4 million, or 9.1%, due to the higher use of algaecides and coagulants in several Water Treatment Plants in the Metropolitan Region of São Paulo in order to maintain the quality of raw water.

Services

Expenses with services totaled R$ 1,772.4 million, a decrease of R$ 36.0 million, or 2.0%, from the R$ 1,808.4 million recorded in 2019. The main decreases were:

The decreases were partially offset by the R$ 46.9 million increase in paving expenses.

Electricity

Electricity expenses totaled R$ 1,217.4 million in 2020, up R$ 74.5 million, or 6.5%, over the R$ 1,142.9 million recorded in 2019. In 2020, the Free Market Tariffs (ACL) accounted for 47.5% of total expenses (36.7% in 2019) while the Regulated Market Tariffs (ACR) accounted for 52.5% (63.3% in 2019).

The main factors that contributed to this variation were:

General expenses

Decrease of R$ 179.5 million, or 15.2%, totaling R$ 998.1 million in 2020, compared to the R$ 1,177.6 million recorded in 2019, mainly due to the following factors:

Depreciation and amortization

Increase of R$ 256.9 million or 14.4%, due to the start-up of intangible assets, in the total amount of R$ 3.7 billion.

Allowance for doubtful accounts

Increase of R$ 316.7 million, due to:

Other operating income (expenses), net

Other net operating revenues and expenses came to a positive variation of R$ 126.4 million, mainly due to:

Financial expenses, net of income

Increase of R$ 108.5 million, mainly due to:

Monetary and exchange variation, net

The effect of net monetary and exchange rate variations in 2020 was R$ 2,024.2 million higher than in 2019, highlighting:

In 2020, there was a decreased by R$ 957.7 million due to the lower taxable income, highlighting:

The Water Loss Reduction Program aims to achieve a consistent loss reduction in the long term, by implementing several operational improvement and maintenance actions, in addition to important actions to renew and improve infrastructure.

As a result of the Program, the total water loss index gradually fell to 27.0% in 2020, corresponding to 263 liters per connection per day.

As from 2021 onwards, the water loss from the municipality of Guarulhos will be accounted for in the index, leading to an increase of approximately 10 liters per connection per day in the total water loss index. Accordingly, the goal for 2021 is reaching an index of 268 liters per connection per day, including the municipality of Guarulhos.

* Unaudited

The following performance Management Indicators show: Gross revenue, operating expenses and EBITDA, all of them per billed cubic meter.

The historical series has been presented since 2014, based on quarterly financial data disclosed by the Company, excluding some non-recurring and significant events that would distort the result.

All indicators were calculated based on average values of 4Q20, adjusted by changes in the IPCA consumer price index, to determine the behavior on a same-price base in the period.

Gross Revenue per billed cubic meter increased, especially after the 3Q15. In 4Q20, it was down by 6.0% from 4Q19.

Operating Expenses per billed cubic meter increased in a controlled manner on a quarterly basis, compatible with the expansion of operations, showing a stable average performance and reflecting disciplined cost management. In 4Q20, it was down by 11.2% from 4Q19.

Finally, the EBITDA per cubic meter increased in the period, basically due to the performance of Gross Revenue and Operating Expenses. The 4Q20 had a positive evolution compared to the beginning of the year, reaching the same level as in 4Q19, despite the impact of COVID-19 on the Company’s revenue.

Total Gross Revenue per m³ Billed - R$/m³

Figures at 4Q20 average prices, updated by IPCA

The following were not considered:

- Construction revenue

- R$928 million referring to the agreement with Guarulhos in 4Q18

- R$1,254 million referring to agreement with Santo André in 3Q19

- R$195 million referring to agreement with Mauá in 2Q20

Operating Expense per m³ Billed - R$/m³

Figures at 4Q20 average prices, updated by IPCA

Expenses considered: personnel, general supplies, treatement materials, services, electricity, general expenses and tax

Reversals excluded:

- R$696 million referring to agreement with the São Paulo State Government in 1Q15

- R$307 million referring to the migration of the supplementary pension plan in 3Q16

- R$173 million referring to the TAC - Retirees in 3Q19

EBITDA per m³ Billed - R$/m³

Figures at 4Q20 average prices, updated by IPCA

The following were not considered:

Revenue:

- R$928 million referring to the agreement with Guarulhos in 4Q18

- R$1,254 million referring to agreement with Santo André in 3Q19

- R$195 million referring to agreement with Mauá in 2Q20

Reversal of expenses:

- R$696 million referring to agreement with the São Paulo State Government in 1Q15

- R$307 million referring to the migration of the supplementary pension plan in 3Q16

- R$173 million referring to the end of the TAC - Retirees in 3Q19

* Unaudited

10. Loans and financing

The Company has frequent access to Brazilian and international credit markets and maintains solid relationships with public banks and multilateral agencies. Such mix and diversity of sources results in an extended debt amortization profile, at costs compatible with its investment cycle, especially those granted by official Brazilian banks and multilateral credit organizations. Continuing with the guidelines approved by the

Board of Directors in 2019 for the management of foreign debt, in order to include initiatives to capture opportunities that decrease the foreign exposure of its debt, at the end of 2020 external indebtedness accounted for 21% of total debt exposed to the exchange variation of the Brazilian real against the U.S. dollar and the Yen, compared to 48% in 2019.

In order to meet its capital needs, the Company carried out its 25th, 26th and 27th debentures issuances at R$ 1.45 billion, R$ 1.05 billion and R$ 1.0 billion, respectively. In April 2020, the Company exchanged US$ 494.6 million debt to R$ 2,810.9 million with the IDB reducing its exposure to the variation of the U.S. dollar. In addition, on September 30, 2020, the Company early amortized Eurobonds in the amount of R$ 1,910.1 million (US$ 357.8 million) to reduce currency exposure and, in November, it entered into an agreement of R$ 950.0 million with IDB Invest.

Covenants

The following table shows the most restrictive clauses in 2020:

As of December 31, 2020, the Company met the requirements set forth by its borrowings and financing agreements.

11. CAPEX

Investments totaled R$ 4,379.5 million in 2020. The investment in 4Q20 was R$ 1,262.0 million.

Cash used in 2020 referring to the Company’s historical investment totaled R$ 3.3 billion.

The chart below shows investments broken down by water, sewage and region.

Between 2021 and 2025, the Company plans investments of R$ 21,0 billion, R$ 8,2 billion of which in water supply and R$ 12,8 billion in sewage collection and treatment.

For more information, please contact:

Mario Arruda Sampaio

Head of Capital Markets and Investor Relations

Phone:(55 11) 3388-8664

E-mail: maasampaio@sabesp.com.br

Angela Beatriz Airoldi

Investor Relations Manager

Phone:(55 11) 3388-8793

E-mail: abairoldi@sabesp.com.br

Statements contained in this press release may contain information that is forward-looking and reflects management's current view and estimates of future economic circumstances, industry conditions, SABESP performance, and financial results. Any statements, expectations, capabilities, plans and assumptions contained in this press release that do not describe historical facts, such as statements regarding the declaration or payment of dividends, the direction of future operations, the implementation of principal operating and financing strategies and capital expenditure plans, the factors or trends affecting financial condition, liquidity or results of operations are forward-looking statements within the meaning of the U.S. Private Securities Litigation Reform Act of 1995 and involve a number of risks and uncertainties. There is no guarantee that these results will actually occur. The statements are based on many assumptions and factors, including general economic and market conditions, industry conditions, and operating factors. Any changes in such assumptions or factors could cause actual results to differ materially from current expectations.

Income Statement

Balance Sheet

Cash Flow