Reading order
| # | Title | Published | Author | Buy on Amazon |
|---|---|---|---|---|
| 1 | Kyssfaktorn | 2018 | Helen Hoang | N/A |
| 2 | The Kiss Quotient | 2018 | Helen Hoang | Buy |
| 3 | Love Challenge | 2019 | Helen Hoang | N/A |
| 4 | The Bride Test | 2019 | Helen Hoang | Buy |
| 5 | The Heart Principle | 2021 | Helen Hoang | Buy |
| 6 | Heart Story | 2022 | Helen Hoang | N/A |
The Kiss Quotient series by Helen Hoang is a fiction series with six books published between 2018 and 2022. The series includes both the original English-language novels and their translated editions, with Kyssfaktorn and The Kiss Quotient both appearing in 2018, followed by Love Challenge and The Bride Test in 2019.
The Heart Principle arrived in 2021, and Heart Story closed out the series in 2022. The main English-language novels are The Kiss Quotient, The Bride Test, and The Heart Principle, each of which can be read as a standalone romance while still sharing characters and settings. Reading them in publication order gives the most complete experience of the world Helen Hoang built across the series.