We updated our style for telephone numbers in 2024 to drop parentheses. We now recommend the form: 212-621-1500. For international numbers use 011 (from the United States), the country code, the city code and the telephone number: 011-44-20-7535-1515. Use hyphens, not periods. No parentheses. The form for toll-free numbers: 800-111-1000. If extension numbers are needed, use a comma to separate the main number from the extension: 212-621-1500, Ext. 2.