World's largest census: India to begin population count

• Documents a population exceeding 1.4 billion, making it one of the world’s largest data exercises.

• Guides policy on housing, energy, food, and urban infrastructure challenges.

• Supports equitable governance and targeted welfare distribution.

• Uses digital tools and multilingual platforms for broader inclusion.

• May reintroduce caste data, shaping social and political debates.

• Provides critical planning benchmarks through 2027 and beyond.

India has embarked on one of the most ambitious administrative undertakings in its history: a nationwide census expected to document a population now estimated at more than 1.4 billion people. The scale and scope of the operation make it one of the largest data-gathering exercises ever attempted anywhere in the world.

Over the coming year, more than three million government personnel will fan out across the country — from densely packed urban neighbourhoods to distant rural hamlets and mountainous terrain. Their mission is to assemble an updated demographic snapshot of a nation experiencing immense social and economic transformation. With India facing mounting challenges linked to rapid population growth — including shortages in housing, energy pressures, and stress on food and water supplies — policymakers are expected to rely heavily on the findings to shape future planning and development strategies.

Officials have characterized the roughly $1.24 billion project as an undertaking of immense national significance. Beyond simply tallying residents, the exercise aims to provide the evidence base needed for more equitable governance and better-targeted welfare programs. The data gathered will likely influence everything from public spending priorities to the design and distribution of social benefits.

The urgency is particularly evident in India’s cities. Several major metropolitan areas continue to grapple with water scarcity, deteriorating air quality, congested infrastructure, and the steady expansion of informal settlements. In such conditions, an accurate population count is seen as essential to informed decision-making.

India last conducted a full census in 2011, when the population was recorded at 1.21 billion. A follow-up count scheduled for 2021 was deferred because of the Covid-19 pandemic, leaving a prolonged gap in official demographic data. In the intervening years, international estimates — including assessments by the United Nations — indicate that India has surpassed China to become the world’s most populous country.

A Two-Stage Operation

The census will unfold in two distinct phases, blending traditional door-to-door enumeration with digital technology.

The first stage, which began last week and will continue through September, centers on housing conditions and access to essential services. Enumerators will visit households directly, while residents will also have the option to submit information through an official mobile application. The digital platform, available in 16 languages, incorporates satellite imagery to assist in mapping and verification — an acknowledgment of the country’s vast linguistic and geographic diversity.

In the second phase, attention will shift to individual-level information, including demographic, social, and economic characteristics.

One of the most closely scrutinized elements of the upcoming count is the proposed collection of caste-related data — a subject that remains politically sensitive. Although caste continues to shape educational access, employment opportunities, and the distribution of public resources, comprehensive caste data has not been officially published in decades. A caste survey conducted in 2011 was never released due to reported inconsistencies.

The last time India included detailed caste information in a census was in 1931, during British colonial rule. Since independence, successive governments have refrained from updating these figures, citing both logistical complexities and concerns that such data could inflame social divisions.

Adjusting to Geography

Given India’s diverse terrain and climate conditions, authorities have tailored the census schedule to different regions. For most of the country, population enumeration will occur in the weeks leading up to March 1, 2027, which will serve as the official reference date.

In contrast, high-altitude Himalayan areas — including the contested territory of Jammu and Kashmir — will be counted earlier, before October 1, 2026. This adjustment is intended to prevent disruptions caused by harsh winter weather and heavy snowfall.

Executing a census in a country of India’s size presents formidable logistical hurdles. Even the 2024 general elections, widely regarded as the largest democratic exercise globally, were organized in seven stages over six weeks. The census, however, will span several months and demand coordination on an even broader administrative scale.

As India undertakes this vast enumeration effort, the outcome will extend far beyond statistical records. The data collected will help define how the world’s most populous nation plans its future — from urban development and infrastructure investment to social justice and economic policy.