The 2020 Census Internet Self-Response (ISR) operation provided an internet data collection instrument that respondents could use at any time from nearly any location to respond online. This application could be used across most devices and browsers and was available in 13 languages. Users could respond with or without a Census ID (Non-ID). More than 90 million responses were collected through the ISR application. The ISR Non-ID option received and processed more than 17.5 million responses during the 2020 Census, nearly double the anticipated workload. 

Before adjustments for COVID-19 were made, the Census Bureau planned to send the following self-response mail materials to households over a period of approximately 6 weeks: invitation and reminder letters, reminder postcards, and questionnaires. The COVID-19 pandemic caused the extension of the 2020 Census data collection period, challenges with the mailing operation that led to mailing delays, and the implementation of two additional mailings to the 2020 Census mail strategy. The Census Bureau extended the deadline for self-response from July 31, 2020, to October 15, 2020, and the ISR instrument remained available to the public throughout this time.

The ISR operation was a resounding success and critical to the overall success of the 2020 Census. The ISR instrument managed the high traffic demand and operated throughout the census without one second of downtime. It was available to the public from 12:00 a.m. Eastern Daylight Time (EDT) on March 9, 2020, to 11:59 p.m. Hawaii Standard Time on October 15, 2020 (5:59 a.m. EDT October 16). The average response time was 9 minutes, 39 seconds. Most respondents, 89.3 percent, submitted a questionnaire the first time they logged into ISR with their Census ID.

Key recommendations for the design of future ISR instruments are as follows: simplify address collection and verification screens to improve the quality of addresses collected through the ISR Non-ID option; provide a user-friendly way for Non-ID respondents to report vacancy status; allow respondents to provide information on housing units that were sent mailing materials but should be considered for deletion; and provide a confirmation screen for a housing unit reported as being vacant, in addition to collecting the respondent’s name and telephone number for potential follow-up about it.