Croatia’s Zagreb Airport Tops 3.6 Million Passengers as Summer Slowdown Puts Winter Travel in Focus

Zagreb Airport in Croatia handled 3,622,547 passengers between January and September 2026, up 1.1% year on year, as strong early growth kept the capital’s gateway ahead despite a weakening summer. September traffic fell 3.3% to 455,530 passengers, marking the third consecutive monthly decline against 2025 and putting the winter travel period in focus.

The airport remains above last year’s cumulative passenger total, but the margin has narrowed. Growth in the first quarter gave way to a decline in the third, while aircraft movements fell across the nine months. For tourism businesses, the figures show a gateway still expanding overall, although recent activity offers a less buoyant backdrop for city breaks, business travel and onward trips within Croatia.

A strong winter gives way to three months of declines

January, February and March generated 917,476 passengers, up approximately 7.1% from 856,966 in the same quarter of 2025. That added 60,510 passengers before the main summer season. January grew 5.8%, February increased 7.8% and March rose 7.5%, establishing the lead that continued to support the nine-month result.

Momentum then weakened. April declined, May recovered modestly and June was almost flat. July, August and September all finished below their 2025 levels. Together, those three months handled 1,402,999 passengers, down approximately 2.0%, or 29,247 passengers. September alone accounted for a reduction of 15,357 passengers. Across April to September, five of the six months recorded either a decline or almost no growth.

Zagreb Airport monthly passenger traffic

Passenger totals follow Zagreb Airport’s published series. ADP’s September release records 3,622,554 passengers for the nine months, seven more than the airport’s total; both report growth of 1.1%.

The monthly table uses the airport’s published figures, including 448,283 passengers in May and 438,571 in June. May’s annual increase rounds to 2.4%. June’s 0.05% rise represents just 209 additional passengers, showing how little growth remained before the three successive declines.

Fewer movements leave a different operating picture

The operational figures reinforce the slowdown. Zagreb recorded 38,284 aircraft movements during January–September, down 2.6%. September accounted for 4,714 movements, a fall of 2.3%. Each movement represents a landing or take-off, so the figures should not be read as numbers of return services.

Key traffic indicators

Sources: Zagreb Airport and Groupe ADP.

Higher passenger throughput alongside fewer movements means the average passenger count per recorded movement increased over the nine months. It does not prove that aircraft seats were fuller. Aircraft size and the mix of commercial and other operations can also change that relationship. Zagreb’s traffic release does not supply a local seat occupancy figure.

Groupe ADP’s wider September commentary identifies higher fuel prices, adjustments to airline capacity and weaker demand conditions across its network. Those are group-level observations. The release does not isolate their contribution to Zagreb’s performance or establish one specific reason for the airport’s decline.

The tourism impact extends beyond the headline total

For hotels, tour operators and destination managers, passenger traffic provides a measure of activity through the capital’s gateway. However, it includes arrivals and departures, residents travelling abroad, business passengers and connecting travellers. A return journey can count twice. The total therefore cannot be treated as the number of foreign tourists visiting Zagreb.

The commercial effect depends on which routes and traveller groups account for the change. The published airport totals do not identify lost hotel nights, lower visitor spending or weaker package bookings. They also do not demonstrate a uniform downturn across Croatia. National statistics recorded 10.25 million airport passengers during January–August 2026, an increase of 2.3%.

Croatia’s August results illustrate that uneven picture. Dubrovnik’s passenger traffic rose 4.0%, while Split declined 3.1% and Zagreb fell 2.4% in the same national statistical series. Coastal destinations and the capital therefore entered the later summer with different patterns. The national data cover an earlier period than Zagreb’s September update and should be compared with that distinction in mind.

Five million capacity keeps airport expansion in focus

The slowdown follows a year in which Zagreb handled 4,721,563 passengers, up 9.4%. That annual total represented approximately 94.4% of the five-million-passenger capacity originally specified for the modern terminal, explaining why infrastructure planning remains relevant even as growth eases.

The terminal began operating on 28 March 2017. Groupe ADP’s opening announcement described a 65,000-square-metre building with eight boarding bridges and an initial capacity of five million passengers annually. It identified potential for capacity to reach eight million after a second development phase, providing room for substantially greater traffic over time.

Annual design capacity does not establish how crowded the airport becomes at particular hours. It cannot, by itself, show that morning or evening peaks prevent additional services. Neither the passenger totals nor ADP’s September release attributes the recent decline to terminal congestion. Expansion requirements and the reasons for weaker traffic therefore remain separate questions.

Concession documents set out the expansion thresholds

Government-published concession documents provide a more detailed framework for future development. The agreement published in 2013 links successive expansion stages to annual passenger thresholds, subject to contractual conditions. The specified thresholds include:

• Phase 2A: at least five million passengers in a calendar year.
• Phase 2B: at least 6.1 million passengers in a calendar year.
• Phase 2C: at least 7.3 million passengers in a calendar year.

The provisions include financing and refinancing exceptions, so reaching a threshold should not be presented as an unconditional construction timetable. The documents also contain other expansion provisions. They establish the framework against which development is assessed, rather than announcing a new start date in response to September’s traffic figures.

The revised technical annex envisages the apron, where aircraft park and receive ground services, expanding from 101,018 to 300,000 square metres between Phase 1 and Phase 2. It also specifies an increase from eight to 16 boarding bridges. These are contractual development specifications, not evidence that the full expansion is currently under construction.

A long concession connects Zagreb with ADP and TAV

Croatia signed the 30-year concession agreement on 11 April 2012, covering construction of the passenger terminal and management of airport facilities. The concessionaire took over management in December 2013. TAV’s airport profile states that operating rights extend until 2042, linking the investment programme to a long operating period.

The corporate structure separates the consortium holding company, ZAIC-A, from MZLZ, the wholly owned concession company. Groupe ADP’s 2024 registration document lists ADP International’s interest in ZAIC-A at 21.89% and TAV Airports’ interest at 15.81%. TAV’s 2026 reporting also identifies its Zagreb holding as 15.81%, providing a more precise picture than the older rounded figures of 21% and 15%.

Groupe ADP also holds 46.12% of TAV, according to TAV’s 2026 shareholder disclosures. This adds an indirect ownership link alongside ADP International’s direct investment in the Zagreb consortium. These holdings explain why Zagreb appears in the groups’ operational reporting, but share percentages alone do not establish sole control over the airport’s concession company.

Winter traffic will decide whether the annual lead survives

Zagreb reached the end of September with 37,730 more passengers than during the corresponding nine months of 2025. That cushion leaves the full-year outcome open despite the summer reversal. The previous year’s final quarter generated 1,136,746 passengers, including 461,562 in October, 340,201 in November and 334,983 in December.

To match the 2025 annual total, the airport would need 1,099,016 passengers between October and December 2026. That is approximately 3.3% below the equivalent 2025 quarter. This is an arithmetic benchmark, not a traffic forecast, but it shows why three weaker months do not automatically mean the airport will finish the year below its previous total.

The next monthly results will show whether the decline stabilises or continues to reduce that margin. Groupe ADP’s published calendar schedules its October traffic update for 16 November 2026. For Zagreb’s travel industry, the next evidence will be whether winter passenger volumes regain momentum and how that performance fits the airport’s longer-term infrastructure requirements.