First, let me disagree with comments saying that this question is not answerable. It is, but with an important note:
There are many factors by which large companies differ from smaller ones.
Each factor may be either a benefit or a disadvantage, depending on your personality.
So, there is no ultimate answer like "go for a large company, period". In the light of SE principle of determining Good Subjective, let's think how each factor works for you who read this answer (simply put, whether it is a benefit or not), and why should you choose a large or a small company, depending on who you are.
What are these factors?
Of course, let's start with money. Studies in 2012 reveal that less than half of small companies (up to 99 employees) offer any benefits to their employees.
It sounds like an objective factor: the more money the better, but it is not that simple because money is not only your salary. See next topics.
In a small company, you often stand on the second level just after the company's owner. This opens great opportunities for you. If you work hard enough, your success will be easily noticeable (see Appreciation below), and you may take a higher position even if you don't have sufficient background, formal education, etc.
Think of it: even if you quit, apply for a new job, and were asked if you have a degree of a position you're applying to, you may respond that you have practical working experience on this position for N months.
Large companies have hierarchy (see below), so you can't easily jump over the steps.
Professional Growth — Opportunity to switch job without leaving
Large companies often have many various positions in place, and some of them are open. If you are passionate about something else (say, you are a Software Developer who wants to try yourself as a QA Engineer), sooner or later you will have such chance.
In a small company you are usually loaded with your current assignments, and it's hard to replace you. So, in order to learn something, you may work overtime, usually with no reimbursement. Decide if you are ready for that.
Professional Growth — Ability to Learn (for free)
Large companies offer their employees some free training and certifications. This may be a great benefit for you, especially if other factors are negative (e.g. if you lack university degree in your field of business).
Professional Growth — Take Ownership of Your Company
When a small company becomes public (IPO), you may be offered to buy shares for a discount price, or as a premium. This will quickly turn yourself from "just a worker" into a co-owner. This totally new level may dramatically change your entire career.
Structure and Hierarchy
Large companies usually have more evident hierarchy and therefore chain of responsibility.
In smaller ones, people often have to take decisions because the very next upper level is the owner of the company who's simply too busy to resolve each minor thing.
Believe it or not, many people do not like to take decisions and be solely responsible for consequences. Others however are not comfortable being a small cog in a big machine, they think it violates their dignity.
Success — Objectives
In a large company, you often work on large projects, but you don't work alone. If one of your colleagues makes the things fail, all your efforts will be discarded.
Working in a small team, you have more chances to intrude and save the project if things are going to fail.
Success — Appreciation and Recognition
In a small company, all your success and failures are visible. Quoting Dean Medley, Senior VP at Medical Methods:
"Every success you have in a small business is magnified by a hundred."
In large companies, changes happen slowly. If you are excited with some bright idea and wish it to happen (to make profit for your company and some respect for you, see above), you have to agree on it with so many people.
However, some people are pretty conservative and they don't like rapid changes. See for yourself.
In smaller companies, everyone knows each other, while in large ones you may not know even those who are working three cubicles away from you. Again, this may be good or bad depending on how much you like to socialize.
If Everything Went Wrong — A Company
Companies occasionally have problems, let's admit it. Large companies are less vulnerable to average- and small-size troubles. A bigger company has a bigger financial base, so it's not that likely to fold quickly.
A small startup may survive paycheck to paycheck. Decide how much risk you are willing to take.
If Everything Went Wrong — Yourself
If you are not doing well in a small company, there are few chances to recover. I had an issue of sending a single wrong email that costs me the whole relationship with the employer.
In a large company, it's not that evident that the failure is yours (see above), so there are more chances to recover.
As you see, there's no rocket science in all topics above. Everyone who has a dilemma of choosing a large company versus a smaller one should think of those factors and decide how each of them matches your personality.
If you prefer a more sophisticated, mathematical approach, do the following:
- Assign each factor a number of 1 to 10, where 1 would mean "I don't really care about this" and 10 stands for "this is critical for me";
- Take a sheet of paper and split it into two columns: "Pros" and "Cons";
- Write down the number into a correspondent column;
- Compare the sums to find what works best for you.