Europe · Boy names
Boy Names That Start with O — Europe
Looking for a baby boy name starting with O that travels well across Europe? This page aggregates names recognised in our 25-country database — 1301 boy names in total, including Oliver, Otto, Omar, Oskar, Oscar. The "in X countries" badge under each name shows how widely it is officially accepted, which matters for expat parents who want a name that works seamlessly from Reykjavík to Rome. Click any name with a link to see its full country-by-country legal status.
1301
Names starting with O
25
European countries
30
Shown below
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Top 30 European boy names starting with O
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FAQ
How many European boy names start with O?
Our database lists 1301 European boy names beginning with the letter O, drawn from official name lists across 25 countries. The top 30 by cross-country availability are shown on this page.
Are these names legally registrable in Europe?
Legality depends on each country's naming law. The "found in X countries" badge on each name indicates how many European countries officially recognise it — names with a high score (e.g. 10+ countries) are safe choices for multicultural families.
What's the most popular European boy name starting with O?
Oliver is the most cross-border boy name starting with O in our database — recognised in 20 of the 25 European countries we track.
Check a name in any European country
Run any of these names through our free legality checker — covers all 25 European countries.
Check a Name →Last updated: 2026-05-13. For informational purposes only. Always consult your local civil registry for definitive answers.