Evidence-based answer · Last updated · How it’s made
None of the sources directly address "how to pause/stop SRS," but they do offer solid, related evidence: vocabulary and skills learned through spacing/retrieval decay slowly rather than catastrophically if you've reached a solid level first, continued (even light) exposure protects what you've learned far better than a full break, and if you must pause, the same spacing principles that make SRS work (long-ish intervals, retrieval-based review, and testing rather than re-reading) should guide how you restart or "relearn" afterward. In short: SRS is safest to stop or pause once items are well-consolidated and some ongoing exposure to the language continues, and after a break you should expect and plan for a deliberate "relearning" phase rather than starting from zero.
Answered for language learning in general. No specific language was set for this question, so the findings are drawn from general second-language research rather than one language’s literature.
A long-term study following advanced learners for 8 years (6 of them after their language courses ended) found that people who kept getting some exposure to the language kept their speaking skills and fluency, and even improved in some areas, while attrition (forgetting/skill loss) was much less than expected overall — even learners with limited ongoing exposure showed little loss.2
In plain terms
The same study found that how advanced someone was at the point they stopped formal instruction ('peak attainment') was itself an important predictor of how well their skills held up later — reaching a higher level before stopping seems to protect against loss.2
Research on missionaries who stopped actively using a foreign language after intensive study found vocabulary was gradually lost over time, but relearning it later was much faster than the original learning — old knowledge leaves 'savings' in memory even after it seems forgotten.1
Example
In a case study where one learner crammed 300 new foreign-language words at a rate of 15 per day over 20 days, the words were nearly all known right after the cramming period, but a large amount was lost in the following weeks — showing that fast, intensive learning without spacing produces knowledge that fades fast once review stops.7
When learners had to relearn vocabulary after a gap, using long spacing (waiting longer between review repetitions) during both the initial learning and the later relearning session produced the best long-term retention — better than short spacing at either stage — even though it took a bit more time.3
In plain terms
Example
Across several controlled studies, spacing out reviews over days (rather than cramming them close together) consistently produced better long-term retention, and one study found it also helped learners apply the vocabulary to new/unseen contexts, not just remember it in the exact form they studied.5,6,9,10,11
None of the available sources specifically studied when to permanently stop using an SRS app, how to wind it down, or best practices for pausing a flashcard system for weeks or months and resuming it — the evidence here is inferred from general research on spacing, vocabulary attrition, and long-term retention rather than from a study of SRS breaks themselves.3,4,8
Now pick something to do it with
Each of these opens an overview of the apps, courses and immersion material worth a look for that — filtered to exactly what the advice above points you at:
Or see the full resource list