I've been told that it is never good to complain on an employee satisfaction survey--even if partly anonymous. The reasoning is that HR may attempt to rectify the situation, which means attention will be focused on my boss, who will then be suspicious and perhaps even guess correctly that the "complainer" is me.
Be honest, balanced and fair. Offer constructive criticism/feedback, including offering possible solutions instead of just complaining about problems. Give praise for things that are done well in addition to pointing out areas for improvement.
If no one brings issues to the attention of people who can get them resolved, they will only get worse. Management should welcome constructive feedback and use it to make the company a better place to work.
If you truly fear retribution, file a more anonymous addendum to the survey by typing, printing & hand-delivering a statement in an unmarked envelope, after hours. But if someone is really bent on figuring out who submitted it, they could probably figure it out from your writing style if they know you well enough.
Yes it is risky to complain. Complaining is essentially a way of saying 'I don't like this, fix it' which is always risky.
What you DO want to do however, is provide feedback. Feedback says 'I don't like XXX because of YYY though i think we could improve this issue by doing ZZZ'
This is much more diplomatic and constructive. Remembering that this is your workplace you want it to be comfortable and you want it to help you be efficient in your job, it is in your best interests to try to improve it but ALWAYS try to provide feedback constructively, it shows that you view this as an issue and that it is impeding you to the point where you have come up with a solution.
This also opens the door right up for them to say, 'Right, here is a potential solution we have been given, do we think this is right?'
In my experience you should provide fair feedback, if you think they are doing something right, say so, if you think they are doing something wrong, also say so, your opinion does matter in a work environment, they are even trying to encourage your opinions out of you with these surveys so by all means give that feedback!
(but remember to be positive about it, negativity always leads towards conflict)
It all depends on how the survey results are used by the HR/employer.
In case you have participated in earlier surveys and have seen some of the comments/suggestions from employees are indeed acted upon by the management, then you can be honest and give a fair feedback. In case you are new to this organization, you might know if this happens from offline discussions with others in your organization on how much responding to these surveys matter.
If this is just one of the things from HR, just to show that they do seek feedback from employees, but historically they have never taken any actions, then it does not matter.
But I would like to caution you, since the survey is not completely anonymous, there might be a risk involved if your inputs are some what skewed from the others and if your inputs indicate something which says that all is not well and you are unsatisfied. The results could be drilled down by HR/your manager and your manager could be able to find out what/whose inputs has made the score come down (if there is a score and your manager is being evaluated using this score).
So it is better to give constructive feedback and ensure that any feedback on issues which are personal to you is not mentioned in your responses. Please be as generic as possible.
While some of this has to do with the corporate culture, your bosses personality and whether you believe they are simply going through the motions or not as others have discussed, some of it depends on the nature of the complaint. (Note most HR organizations do try to keep the surveys annonymous, but by the nature of identifying the demographic information some people are less annonymous that others - I am the only female over 55 in my department for instance)
In my experience it is rare for anyone to get into trouble with the numeric ratings for a department or working group(rate the HR department on a ascale of 1-5) even when they rate very low. Where you need to be careful is on the questions (or in your comments) where the items are easily personally identifiable. For instance if you say there is a lot of sexual harrasmenet in your department and you are the only woman in the department, it will be obvious who said that. In this case you need to treat the questions just as if you were reporting an issue in person. If you would go to HR with this issue (or have done so), then reporting it on the survey will work for you. If you would be afraid to report the issue in person and your answer will be readily identifiable to you, then don't bring it up on the employee survey.
If you want to make comments that are negative and specifically about a person (not just a general dislike of the current health insurance for instance), do not make them unless you would feel comfortable bringing them to your boss in person. And if you would feel comfortable talking to your boss in person, why haven't you? That is usually a better way to get issues resolved than in an annonymous survey.
I would concentrate my negative feedback to organizational entitites outside my own and to things which affect the organization as a whole such as benefits, payraises, etc. Keep specifics about a specific person or personal situation to yourself and handle through other channels in the workplace if you feel you must.
I am sure it is different from place to place. I had one bad experience a couple of years ago when working at a company that I first considered a results driven meritocracy until they hired a manager from outside who was nearly 60 years old, old school, and forcing conformism and military-style drills on everyone. They handed out something like team effectiveness surveys with questions such as "How do you rate communication style" and "How effective is the workflow management" etc. to which I gave my objective assessments, not personal complaints. The survey was communicated via email to HR and I was under the impression it would be anonymous, as much as the small environment allows. Next team meeting, the authocratic manager brought everyone's survey sheet printed out with the names on them and laid them on the table like cards in a poker game, hinting at the correlation between the survey feedback and the person's committment to the infalliibility of the team supervision, i.e. dogmatic and unquestioned obedience. Next month, I was laid off.
YMMV -- and hopefully does from mine