A Little Reminder Can
Go A Long Way
A behaviorally informed The first treatment group received a standard bill notification
message from COMPESA, while the other treatment groups
SMS experiment minimized received messages informed by a previous behavioral diag-
nostic that had uncovered insights about some of the beliefs
commercial water losses held by clients about water supply or bill payment. The SMS
in the Recife Metropolitan reminders were sent for three months, from November 2019
to January 2020. Clients received the exact same message in
Region of Brazil, by increasing each month, except for those in the seasonal group by design
(Table 1).
on-time payment rates and TABLE 1: Treatment groups and messages in SMS experiment
total amount paid to promote water bill payment in Recife, 2019-20.
GROUP MESSAGE DESCRIPTION
No bill notification message,
Control No message
Water scarcity remains common in Brazil, especially equivalent to a pure control.
in the Recife Metropolitan Region (RMR) in the State
“…your invoice due
of Pernambuco. The RMR is subject to particularly on xx/xx/xxxx of
Standard Standard bill notification
high levels of non-revenue water—which occur when property xxxxx
notification message from COMPESA.
high volumes of water produced do not generate is now available
revenue for the supplier. While some losses may be for payment.”
due to structural and operational inefficiencies such Hard work by COMPESA
as leaky pipes, clients also play a key role by default- is highlighted to counteract
“…we are working
ing on their water payments or installing bypasses to Reciprocity hard to bring water
client’s justification of late
consume water free of charge. This has a significant payments as a response
to your family….”
to receiving what they
and detrimental impact for COMPESA, the Pernam- view as poor service.
buco State Water Supply and Sanitation Company.
Clients are reminded of
COMPESA, as well as the World Bank’s Water Global Prac- what could happen if
“...avoid having
they fail to pay, as the
tice and Mind, Behavior, and Development (eMBeD) teams, Deterrence your name sent to
consequences of not
with financing from the United Kingdom Prosperity Fund, credit bureau...”
paying are rarely perceived
partnered on a behavioral diagnostic and pilot experiment to as credible by them.
reduce non-revenue water losses through behavior change.
“…the majority of
This project provides evidence that a short-term, low-cost
people in Greater Beliefs are corrected, as
intervention—sending behaviorally informed SMS —has Descriptive Recife pay COMPESA most clients incorrectly
potential to increase on-time bill payment rates resulting in norm on time. Don’t be believe that the majority of
an increase in the utility’s revenues. part of the minority people do not pay their bill.
that don’t pay…”
Nov 19: “…enjoy
The Project your 13th salary and
catch up payments
with COMPESA…”
Dec 19: “…Merry
Christmas and a Seasonal events, such
A sub-set of almost 211,000 residential clients were ran- Happy New Year as the new year, are
domly assigned to one of five treatment groups or a control Seasonal
for you and your used to promote a
group. Clients in treatment groups received an SMS remin- family. Start 2020 change in behavior.
der before their due date1 with one of five different mes- debt free...”
sages encouraging them to pay their water bill. The control Jan 20: “…we loved
group did not receive a reminder. to serve you in 2019.
We are here to make
2020 even better…”
1. In each treatment group, clients were randomly assigned to receiving the
SMS reminder either one or three days before due date. Despite these timing
difference, results have shown that timing of the SMS reminder had no statistically Note: All SMS started with “COMPESA informs: Mr(s). FIRST NAME”, and all
significant effects on the outcomes. behaviorally informed SMS ended with “Please pay your bill due xx(day) /xx(month).”
The Results
PAID
Behaviorally informed SMS increased on-time payment The most effective messages were the reciprocity and
rates. Clients that received a behaviorally informed SMS deterrence SMS. Both had statistically significant and
were more likely to pay their water bills on time than positive results on the on-time payment rate and total
clients that did not receive a message. Namely, for every amount paid. For example, for every 1,000 clients that
1,000 clients that received the behaviorally informed SMS, received the reciprocity and deterrence SMS, 11 and 6.5
the benefit of these SMS ranged from 6 to 11 additional additional clients, respectively, paid on-time compared
clients paying on-time compared to those that did not to those that did not receive an SMS. Furthermore, when
receive an SMS. While COMPESA’s standard notification comparing effects of behaviorally informed messages
reminder increased on-time payment rates, this effect is not against the standard COMPESA SMS, only the reciprocity
statistically significant, though the other messages were. This message led to a statistically significant increase on on-time
may be because clients are used to receiving the standard payment rates.
message (habituation effect).
The intervention has potential to generate significant
Behaviorally informed SMS increased total amount paid. dividends at a low cost. When extrapolating the on-time
Both the deterrence and reciprocity SMS had an effect on payment rate findings of the best-performing reciprocity
total amount paid. Taking the reciprocity SMS as an example, message to the larger population of clients in the RMR who
the intervention led to an average increase of R$1.7 per default on their water bills, an estimated additional 6,400
bill paid at an average cost of four centavos (R$0.04) per households per month would pay their bills on time should
message. This is equivalent to a return on investment of 41. these results persist.
While both the seasonal and descriptive norm messages
increased the total amount paid, this effect was not
statistically significant.
Policy Implications
In a context where water availability is scarce, minimizing non- The results are also important as studies indicate that clients
revenue water is a key policy priority. Since, historically, only increase their willingness to pay when companies demonstrate
slightly more than half of residential clients pay their water a genuine effort to improve product or service quality. Thus,
bills by the due date, COMPESA’s ability to properly operate there could be additional positive dividends, as COMPESA’s
and maintain its infrastructure is hampered. role in this pilot signals a commitment to improving their
internal processes.
COMPESA’s pioneer initiative to use behaviorally informed
interventions in Brazil shows the promising impact of Given the promising results obtained for the reciprocity
using SMS to remind and SMS, piloting slightly different
encourage clients to pay COMPESA’s pioneer initiative to use framings of this message could
their water bills on time. It lead to additional positive gains
demonstrates the potential
behaviorally informed interventions in Brazil over the short-term at very
for increasing payments in shows the promising impact of using SMS little cost as well as contribute
a cost-effective and simple messages to promote water bill payment. to solidify the integration of
manner and by leveraging this methodological approach
existing processes. Future into operations. Together,
analysis and experimentation are necessary, as not all SMS COMPESA and the World Bank plan to trial additional
reminders were received or necessarily read. It will also be behavioral interventions – SMS and beyond – that can
important to assess if the results persist over time and which reduce non-revenue water and be sustainably integrated into
type of clients were more affected by the SMS. COMPESA’s operating model.
About eMBeD
The Mind, Behavior, and Development Unit (eMBeD), the World Bank’s behavioral
science team in the Poverty and Equity Global Practice, works closely with project
teams, governments, and other partners to diagnose, design, and evaluate behaviorally
informed interventions. By collaborating with a worldwide network of scientists and
practitioners, the eMBeD team provides answers to important economic and social
questions, and contributes to the global effort to eliminate poverty and enhance equity.
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Last Update: April 30, 2021.