According to Universal Music Japan, OPEN UP AND SAY ... AHH by POISON has sold 8,000,000 copies worldwide. The album sold best in United States (5,650,000 copies), Canada (400,000 copies) and United Kingdom (100,000 copies).
OPEN UP AND SAY ... AHH certifications and sales
| Country / region | Sales | Certification / source | Certification date / sales as of | |
 Canada |
400,000 | 4x Platinum | 1990 |
Canada Sales: 400,000
Certification / note: 4x Platinum
Certification Date / sales as of: 1990
|
 New Zealand |
15,000 | 1x Platinum |
New Zealand Sales: 15,000
Certification / note: 1x Platinum
Certification Date / sales as of:
|
|
 United Kingdom |
100,000 | 1x Gold | 17 May, 1989 |
United Kingdom Sales: 100,000
Certification / note: 1x Gold
Certification Date / sales as of: 17 May, 1989
|
 United States |
5,650,000 | 5x Platinum | 21 October, 1991 |
United States Sales: 5,650,000
Certification / note: 5x Platinum
Certification Date / sales as of: 21 October, 1991
|
| Worldwide sales | 8,000,000 | Universal Music Japan |
Total
Sales: 8,000,000
Source: Universal Music Japan
|
Year-end chart performance for OPEN UP AND SAY ... AHH
| Chart 1988 | Rank |
 Australian Albums (ARIA) |
16 |
| Canadian Albums (RPM) |
56 |
| US Albums (Billboard 200) |
23 |
| Chart 1989 | Rank |
| Australian Albums (ARIA) |
26 |
| Canadian Albums (RPM) |
40 |
| New Zealand Albums (RMNZ) |
10 |
| US Albums (Billboard 200) |
20 |