SUDDENLY by BILLY OCEAN has sold 2,400,000 copies in Canada, United Kingdom and United States.
SUDDENLY certifications and sales
| Country / region | Sales | Certification / source | Certification date / sales as of | |
 Canada |
300,000 | 3x Platinum | 1988 |
Canada Sales: 300,000
Certification / note: 3x Platinum
Certification Date / sales as of: 1988
|
 United Kingdom |
100,000 | 1x Gold | 2 July, 1985 |
United Kingdom Sales: 100,000
Certification / note: 1x Gold
Certification Date / sales as of: 2 July, 1985
|
 United States |
2,000,000 | 2x Platinum | 5 September, 1985 |
United States Sales: 2,000,000
Certification / note: 2x Platinum
Certification Date / sales as of: 5 September, 1985
|
| Total sales | 2,400,000 | (in 3 countries) |
Total
Sales: 2,400,000
(in 3 countries)
|
Year-end chart performance for SUDDENLY
| Chart 1984 | Rank | Sales |
| Canadian Albums (RPM) |
90 | |
| Chart 1985 | Rank | Sales |
| Canadian Albums (RPM) |
46 | |
 Dutch Albums (Album Top 100) |
73 | |
| UK Albums (Music Week) |
66 | 150,000 |
| US Albums (Billboard 200) |
8 |