Short Answer
The most reliable source of a discount is Duolingo itself. Duolingo occasionally shares limited-time coupon codes directly, and prep platforms and university partners sometimes distribute additional discount codes tied to Duolingo's affiliate or partner programs.
Ways to Reduce the Cost
- Buy the two-test bundle — this brings the per-test price down from around $70 to about $59, without needing any code at all.
- Watch for Duolingo's own promotional emails if you already have an account — they occasionally run limited-time discounts.
- Check prep platform partner discounts — some official Duolingo prep partners offer registration discounts as part of their affiliate relationship with Duolingo.
- Apply for a fee waiver if you qualify financially — see our guide to the DET fee waiver for eligibility.
What to Watch Out For
Be cautious of any site promising a "guaranteed" discount code with no clear source — legitimate coupon codes come from Duolingo directly or from its verified partner platforms, not from random forum posts or unofficial resellers.
Related Reading
For the full breakdown of pricing options, see our DET cost guide.