Market Research Companies in Istanbul

Key figures for researchers

Population

15,754,053, or 18.3% of Turkey’s population (31 December 2025)¹

Districts

39; the largest, Esenyurt, has 1,003,905 residents, and half the population lives in 12 districts (2025)²

Density

2,943 people per km² (2025)³

Province of registration

only 2,123,134 residents are registered in Istanbul; next come Sivas (758,939), Kastamonu (545,503) and Ordu (520,192) (end of 2025)⁴

Internal migration

329,912 people moved in and 371,258 moved out in 2025 (net −41,346)⁵

Syrians under temporary protection

405,016, the highest of any province (2 April 2026)⁶

Fastest-growing districts

Tuzla (+40.5 per thousand), Arnavutköy (+38.7), Silivri (+33.4) in 2025; Istanbul overall +3.3⁷

Economy

29.2% of Turkey’s GDP and the highest GDP per capita of any province, TRY 802,669 (2024)⁸

Rail transport

about 4 million rail passengers a day, 42.9% of public transport use (2025, İBB)⁹

Religious holidays 2027

Ramazan Bayramı 9–11 March; Kurban Bayramı 16–19 May¹¹

Research guide

Research landscape

Istanbul is the main location for market research in Turkey: full-service agencies, qualitative specialists, B2B and healthcare firms, CATI studios, field networks and online panel providers, many of them also coordinating fieldwork in other Turkish cities and neighbouring countries. With 29.2% of Turkey’s GDP in 2024 and the highest GDP per capita of any province, the city is also the first choice for B2B, retail, financial services and media research.

Who you will interview

Istanbul is a city of migrants from the rest of Turkey: at the end of 2025, only 2,123,134 of its 15.75 million residents were registered in Istanbul itself, the rest in their family’s province of origin, led by Sivas, Kastamonu and Ordu. Movement continues in both directions: 329,912 people moved in and 371,258 left in 2025.

Turkish is the fieldwork language for almost all studies. The city also had 405,016 Syrians under temporary protection in April 2026, more than any other province: studies of this group may need an Arabic version. For Kurdish-speaking and other minority audiences, see the Turkey guide. Results for Istanbul often differ from national averages, so an Istanbul boost on a national sample is common when Istanbul findings matter.

Fieldwork in practice

Istanbul has 39 districts of very different size and profile: Esenyurt alone has 1,003,905 residents, and half the population lives in just 12 districts. Sampling by district, and by the European and Asian sides of the Bosphorus, helps control the spread of interviews. Growth is uneven: in 2025, outer districts grew much faster than the city as a whole (Tuzla +40.5 per thousand, Arnavutköy +38.7, Silivri +33.4, against +3.3 for Istanbul).

Istanbul is dense, with 2,943 people per km². In apartment buildings and gated housing complexes (sites), access often depends on a building manager or security staff. Face-to-face studies usually need permission planning, more contact attempts and more time. Travel times across the city are long: rail now carries about 4 million passengers a day and 42.9% of public transport use, so interviewer routes and central locations near rail lines save time.

Focus groups and qualitative research

In-person focus groups are usually held in dedicated facilities with a one-way mirror and video streaming. Choose the facility side of the city according to the target, since crossing the Bosphorus at peak hours can deter respondents, and allow for travel time when scheduling evening groups.

Ask the agency for its Istanbul incentive levels, recruitment lead times and how it checks that respondents have not taken part in recent groups. B2B and senior respondents often prefer online interviews; online communities and video interviews are widely used, alone or alongside in-person groups.

Timing

The religious holidays move each year with the Islamic calendar. In 2027, Ramadan starts on 8 February, Ramazan Bayramı runs from 9 to 11 March (eve on 8 March) and Kurban Bayramı from 16 to 19 May (eve on 15 May). Avoid the holiday days and the days around them, when families and business respondents are harder to reach. During Ramadan, evening groups and interview times may need adjusting. Summer holidays and school breaks are covered in the Turkey guide.

Working with an Istanbul agency

• Share a clear brief: objectives, target, sample size, districts or sides of the city, method, languages and deadline.
• For face-to-face or recruitment, ask how the agency gains access to apartment buildings and gated complexes, and how it covers fast-growing outer districts.
• For focus groups, ask for the facility address and side of the city, viewing room capacity, streaming options and incentive levels.
• Check fieldwork dates against Ramadan and the two Bayram holidays; ask how long the quote is valid and in which currency.
• Compare several proposals: you can send one request to up to 5 Istanbul companies from this page.

National rules (data protection, holidays, sampling across regions) are covered in our guide to market research in Turkey.