Positive transfer, also called facilitation, occurs when properties of the learner's first language support, accelerate, or simplify L2 acquisition. A Spanish speaker learning English finds the cognate vocabulary, SVO word order, and Latinate academic register already partially available; an English speaker learning Dutch starts with a substantial overlap in lexis and syntax. The term forms the positive half of the pair introduced by Lado (1957), where similarities between L1 and L2 are predicted to facilitate and differences to impede.
Like its negative counterpart, positive transfer is detectable across every linguistic level (Jarvis and Pavlenko 2008):
Positive transfer can also operate at the metalinguistic level: learners who have already acquired one foreign language transfer learning strategies, awareness of grammar as a system, and tolerance for ambiguity to subsequent languages.
Early SLA research focused heavily on errors because errors are visible and tractable. Positive transfer leaves no trace in production: a learner getting something right because their L1 supports it looks identical to a learner getting it right through L2 acquisition. Ringbom (2007) argued that this asymmetry led the field to systematically underestimate L1 facilitation and overestimate L1 interference. He showed that Finnish-speaking learners of English struggle far more than Swedish-speaking learners, despite similar instructional conditions, precisely because Swedish is typologically close to English and supplies extensive positive transfer that Finnish does not.
The most robustly demonstrated form of positive transfer is the cognate effect. Bilinguals process cognates faster than non-cognates, learn cognate vocabulary more efficiently, and retrieve it more accurately. The effect is asymmetrical: it is stronger when the L2 word resembles a high-frequency L1 word, and stronger when the form similarity extends to both spelling and pronunciation rather than only one.
Positive transfer is not automatic. Learners may fail to exploit it when:
Kellerman (1979) showed that even where L1 transfer would produce correct L2 output, learners sometimes resist using L1 patterns they perceive as too language-specific to transfer.
For Vietnamese learners, positive transfer is real but uneven. Vocabulary in technical, academic, and modern-life domains overlaps with English through Latinate roots (often filtered through French) and direct English Anglicisms: marketing, email, online, taxi, café, radio. SVO word order matches. Question intonation patterns are recoverable. Less helpfully, Vietnamese morphology, phonology, and tense-aspect systems share little with English, so positive transfer thins out beyond the lexical and gross-syntactic level.
Useful teaching moves activate latent positive transfer rather than assuming it. Explicit cognate-awareness training (Otwinowska 2015) raises learners' tendency to notice form-meaning correspondence; pre-teaching that flags shared roots converts unconscious familiarity into deliberate recognition; treating the L1 as a resource for hypothesis-formation rather than a contaminating influence aligns with multi-competence and translanguaging perspectives.