A good onboarding period delivers employees who are more satisfied, perform better and are less keen to leave. That is the finding of a meta-analysis of 183 studies on new employees. The most important thing is that a new employee quickly feels accepted by colleagues. Guidance from an experienced colleague is the strongest tool for that.
In short
- New employees who feel accepted, know their role and feel they fit in are clearly more satisfied and less keen to leave.
- According to the latest review, guidance from a mentor or experienced colleague is arguably the most important part of onboarding.
- The law requires you to put the main terms in writing within a week, and to offer mandatory training free of charge and in working time.
About the figures in this article: many figures are correlations. A correlation measures how strongly two things go together, from 0 (no link) to 1 (complete link), and is negative when one rises while the other falls. A correlation does not prove a cause.
In this article
What does a good onboarding period deliver?
More satisfied employees who perform better and are less keen to leave. The most recent meta-analysis, with 183 studies on new employees, found that a good start clearly goes together with job satisfaction, commitment, performance and well-being (Bauer et al., 2025). A meta-analysis is a study that combines the results of many earlier studies.
The research measures a good start by four things: the new employee feels accepted by colleagues, knows their role, has mastered their tasks and feels they fit in with the company. Of those four, fitting in was most strongly linked to job satisfaction (0.46), followed by acceptance by colleagues (0.42) (Bauer et al., 2025).
The wish to leave is also linked to it. New employees who felt they fitted in wanted to leave less often (correlation minus 0.31), as did employees who felt accepted (minus 0.27) or knew their role (minus 0.25) (Bauer et al., 2025). The links with actually leaving were smaller, between minus 0.09 and minus 0.16, but present.
What matters most in onboarding?
That the new employee feels accepted by colleagues. In the latest review, social acceptance was the only feature linked to all outcomes: satisfaction, commitment, wish to leave, performance and well-being (Bauer et al., 2025). The researchers call it the most important mechanism for a successful start.
That is a shift compared with earlier research. A meta-analysis from 2007 measured a good start by role clarity, self-confidence and acceptance (Bauer et al., 2007). According to the new researchers, earlier reviews saw acceptance as roughly as important as the other features (Bauer et al., 2025). Role clarity means that someone knows what is expected of them. It remains important for satisfaction and well-being, but counts for less in performance (Bauer et al., 2025).
What works best in onboarding?
Guidance from a mentor or experienced colleague. The researchers call mentoring and support arguably the single most important part of a successful start, because it was linked to every outcome, including performance and well-being (Bauer et al., 2025). They advise treating guidance as the cornerstone of every onboarding programme.
A fixed approach also helps. Onboarding where experienced colleagues act as role models and the newcomer's own identity is affirmed was strongly linked to role clarity (0.46) and to the feeling of fitting in (0.47). A fixed sequence of steps and a fixed timeline was linked to role clarity (0.43) (Bauer et al., 2025).
What does the most damage is obstruction. New employees who were undermined by a colleague or manager felt much less accepted (minus 0.42) (Bauer et al., 2025). So placing a new employee next to a colleague who has no interest in it can do more harm than good.
Do new employees stay longer because of good onboarding?
Probably, through the bond with the company. A study at a large financial services firm found that onboarding in a group, with a fixed timeline and with affirmation of the newcomer, tied employees more strongly to their work. That bond in turn was linked to less leaving (Allen, 2006).
Support from several sides adds up. A study that followed new employees in seven organisations four times found that support from the organisation, from the manager and from colleagues each made its own contribution to a good start. Through that start, it was linked to commitment, less withdrawal and less leaving (Kammeyer-Mueller & Wanberg, 2003).
Note what this research does and does not show. It is mainly about association, not experiments. So it is plausible that good onboarding makes people stay longer, but it has not been proven exactly how many departures you prevent.
What can a new employee do themselves?
A lot, and you can encourage it. New employees who take the initiative themselves settle in better. Approaching situations positively was most strongly linked to acceptance by colleagues (0.49). Asking for feedback (0.32) and looking for information themselves (0.25) were also linked to it (Bauer et al., 2025).
You can make that easier by saying clearly that asking questions is normal, and by scheduling a fixed moment to look back. A new employee who does not know who to turn to will be slower to ask their questions.
What do I have to arrange legally when someone starts?
You must provide the main terms in writing or digitally no later than one week after the start. These include the job, the start date, the place of work, the pay, the working hours and the probation period. The other details, such as holidays, termination and pension, follow within a month (article 7:655 of the Dutch Civil Code). If they are already in a written contract, you do not need to provide them again.
A probation period (a period at the start during which you and the employee can end the contract immediately) must be in writing and the same for both parties. With a permanent contract, it may last no more than two months. With a temporary contract of more than six months and less than two years, it is one month. With a contract of six months or less, you may not agree a probation period (article 7:652 of the Dutch Civil Code).
Training that you are required by law or by the collective agreement to provide so that the work can be done must be offered free of charge. That training counts as working time and takes place during working hours where possible. An agreement under which you recover its cost from the employee is void (article 7:611a of the Dutch Civil Code).
The key point: the law covers the paperwork, the research shows what really matters. A new employee who has a fixed guide in the first weeks, knows what is expected of them and feels welcome has the best chance of staying and performing well.
Sources
- Bauer, T.N., Erdogan, B., Ellis, A.M., Truxillo, D.M., Brady, G.M. & Bodner, T. (2025). New horizons for newcomer organizational socialization: A review, meta-analysis, and future research directions. Journal of Management, 51(1), 344-382 (online 2024). doi.org/10.1177/01492063241277168
- Bauer, T.N., Bodner, T., Erdogan, B., Truxillo, D.M. & Tucker, J.S. (2007). Newcomer adjustment during organizational socialization: A meta-analytic review of antecedents, outcomes, and methods. Journal of Applied Psychology, 92(3), 707-721. doi.org/10.1037/0021-9010.92.3.707
- Allen, D.G. (2006). Do organizational socialization tactics influence newcomer embeddedness and turnover? Journal of Management, 32(2), 237-256. doi.org/10.1177/0149206305280103
- Kammeyer-Mueller, J.D. & Wanberg, C.R. (2003). Unwrapping the organizational entry process: Disentangling multiple antecedents and their pathways to adjustment. Journal of Applied Psychology, 88(5), 779-794. doi.org/10.1037/0021-9010.88.5.779
- Dutch Civil Code Book 7, article 655 (written statement of terms for the employee), in force on 14 October 2026 (in Dutch). wetten.overheid.nl
- Dutch Civil Code Book 7, article 652 (probation period), in force on 14 October 2026 (in Dutch). wetten.overheid.nl
- Dutch Civil Code Book 7, article 611a (training), in force on 14 October 2026 (in Dutch). wetten.overheid.nl