What researchers have studied
Researchers have studied future-self thinking, planning and writing for years. The results are interesting, but they are not a verdict on whether a letter will change your life. This article covers five studies, what each one measured, and where the claims stop.
The five cover different parts of the question:
- Hershfield and colleagues, 2011, on images of the future self and saving money.
- Hershfield, 2011, a review of how people relate to their future self.
- Gollwitzer and Sheeran, 2006, a meta-analysis of if-then plans.
- Frattaroli, 2006, a meta-analysis of expressive writing.
- Sugimori, Yamaguchi and Kusumi, 2024, on writing to a past or future self.
None of these studies tested Letter to Future Self, so nothing here is evidence about this service. Several were small experiments with particular groups of people, so their findings apply to those groups first.
Future self and today's choices
In the 2011 study by Hershfield and colleagues, people who saw age-progressed images of themselves chose to put more toward retirement savings than people who did not. The experiments were short and run in controlled settings, so they show an effect on a choice in the moment, not on what anyone saved in the years that followed.
A 2011 review by Hershfield, in the Annals of the New York Academy of Sciences, pulls these ideas together. It says people are more willing to make choices that help their later self when that self feels similar, vivid and positive. Calling it a review matters. It summarizes thinking rather than adding a new experiment.
For a letter, this points to one habit: describe your future self as a specific, real and kind person.
Plans and goals
This is the part of the research with the strongest support. In 2006, Gollwitzer and Sheeran published a meta-analysis of implementation intentions, which are if-then plans. An if-then plan names a situation and a specific action, such as “If it is Tuesday evening, I will close the laptop by 9:00.” Across the studies they reviewed, these plans had a medium-to-large average effect on reaching a goal, with a Cohen's d of 0.65.
That number describes an average effect across many studies and tasks. It is not a success rate. It does not mean that a plan makes you far more likely to reach your goal, and it does not mean the plan works for everyone in every case. It does suggest that a specific if-then plan is worth writing down. If your goal is hard to measure, choose a plan with a visible action, such as a walk or a phone call, so you can tell afterwards whether it happened.
Writing about hard things
Expressive writing is the research term for writing about emotional experiences. In 2006, Frattaroli published a meta-analysis of 146 randomized studies of expressive writing. The average effect was positive but small, with a correlation of .075.
That is a useful correction to the idea that writing about feelings reliably helps. The benefit is real on average, but it is modest, and the studies differ from one another in many ways. A letter about a hard season may feel helpful without changing much else, and that is still worth something. Do not expect a single letter to carry more weight than it can.
If you try it, write about the hard thing in plain words for about 15 minutes, then stop. Reread it the next morning, and notice whether the words still fit. The 15-minute limit is our suggestion, not a finding from these studies.
The caveat: the past-self letter did more for mood
The most recent study here carries the clearest warning. In 2024, Sugimori, Yamaguchi and Kusumi reported an experiment with 150 university students in Japan. Each student wrote a compassionate letter to a past self and one to a future self.
In that experiment, the letter to the past self lowered negative feelings more than the letter to the future self did. The study involved university students in one country, so treat it as a reason for care rather than a verdict on future-self letters.
In practice, keep the tone kind, and avoid writing a checklist of worries for your future self to open alone. If you notice that you feel worse after writing, put the draft aside and come back to it later, perhaps on a different topic. If writing about the future leaves you feeling distressed, pause and talk with a doctor or counselor. If you are in crisis or feel unsafe, contact a local emergency number or a crisis line now.
How to use the research in your own letter
If you want to bring the science into your draft, keep these four principles in mind:
- Describe your future self in specific, positive detail.
- Write one if-then plan for each goal you care about.
- Name one hard thing in plain words, without a list of failures.
- Keep the tone kind, and leave out any checklist of worries.
Here is a short example that follows these choices. It avoids pressure and says plainly what the writer does not yet know.
Dear future me,
I do not need to know who you will be yet. I only want to describe the person writing this, so you can see what changed.
Right now I am working longer hours than I like, and I am not sure the job is right. I have one plan: on Tuesdays, I leave the laptop at my desk at six. If that does not happen, I will write down why and try again next week.
I am also tired of pretending this is fine. So I am saying it plainly here.
[your name]
A letter is a small, personal act. No study here followed a letter like this one to see whether it changed savings, goals or mood over time.
Write it now
Write a short letter that describes your future self in specific detail, with one if-then plan and one hard thing said plainly. Keep the tone kind, with no pressure and no list of failures. Then choose the day it should arrive, and keep your own copy, because the success message does not include the text.
