The structural reason Istanbul is excellent for budget travellers is simple: the Turkish lira's long-term weakness against the euro and dollar has made Turkish prices exceptionally competitive for hard-currency visitors. A hotel that charges 3,000 TL/night sounds expensive in lira terms but converts to roughly €85 at current rates — positioning Istanbul's mid-range as a genuine luxury alternative for budget-conscious European and American visitors.
Sultanahmet has the densest concentration of affordable hotels in a historically significant location anywhere in Europe. The streets around the Blue Mosque and the Hippodrome are lined with small hotels, hostels, and guesthouses that charge €40–80/night for rooms with rooftop terrace access, Turkish breakfast included, and walking distance to monuments that would cost €20/hour to queue for in peak season. The trade-off is room size — Sultanahmet's budget properties are often in converted historic buildings where room dimensions are genuinely small.
Karaköy's regeneration has produced a category of stylish budget and mid-range hotels — properties like 10 Karaköy and Vault Karaköy occupy heritage buildings with design credentials that their prices don't suggest. These are genuine value-for-money options that would be classified as boutique in London or Paris.
For pure budget travel, the Hostel category in Istanbul is among Europe's best — properties like Istanbul Hostel in Sultanahmet and Cheers Hostel in Beyoğlu offer dormitory beds in extraordinarily central positions, with rooftop terraces, free Turkish breakfasts, and booking systems that compete with the best European hostel operations.
Practically, Istanbul's budget advantage extends beyond accommodation: transport is extremely cheap (metro single fare around €0.50), street food is excellent and inexpensive (simit breads, gözleme, köfte sandwiches all under €3), and the major attractions are very affordable by European museum standards. A family of four can have an extraordinary Istanbul experience on €150/day all-in including accommodation.