Advice on differential pay
I am currently working an agency tempt doing admin in a UK university. There are four other temps from the same agency who work in the same sub-department as me and we all perform similar roles with minor differences due to how the workload is divided.
During conversations we have had amongst ourselves over the past week, we have discovered that we are on three different rates of pay. We have thus organised a few informal meetings in order to discuss taking some kind of action over this as we feel that the differences in our respective roles are not sufficient enough to warrant differential pay rates (as aside there is a temp from another agency who sits next to us who gets over £2 more per hour for also doing very similar work). We all agreed that it would be better to act collectively and thus initially we decided to send an email to the agency asking what the reasons were for the discrepancies in pay and stating that we felt that we should all receive equal pay. However, one of our group decided that, although she supported what we were doing in theory, she was not willing to take the risk of confrontation by signing the email. This was obviously problematic as it potentially weakened our position. However, the four us decided that we still wished to pursue the matter and so we went ahead with our initial plan.
We received a fairly quick reply from the agency which:
1. Mildly reprimanded us for discussing our rates of pay amongst ourselves.
2. Stated that the rates of pay are based on the job descriptions and decided jointly by the university and the agency so as to reflect the responsibilities laid out in these descriptions. Now I know that not all of us received any proper job description and were basically just told it would be data entry work. Further, they seem to overstate the case as to how much thought has been put in to allocating roles to particular individuals. My impression is the workload has just been divided amongst us in an ad-hoc fashion and in any case is not complex enough to warrant any particular skills beyond accuracy and attention to detail.
3. Offered to consult with the university HR department and share our concerns with them. It then stated that we may get a positive outcome but of course emphasised that we may instead risk a pay cut.
4. Ended by of course asking that in future we come to the agency individually with any problems and not consult amongst ourselves so as to avoid “bad feeling”, before reassuring us that the agency wants the best for us (of course they do!).
My three co-workers are pretty keen to pursue this further despite the risk. One guy in particular has been really enthusiastic about the whole thing which has been heartening to see. In our fist meeting he made a semi-serious discussion about going out on strike which then led us into a general discussion about industrial action. Funnily enough that morning I had be been reading an FAU pamphlet which had an account of a strike in a factory by temps over differential pay rates. I shared this with group and they were all interested by it.
So basically I just wanted some advice over how we should pursue things from here? Any opinions on what our likelihood of success is with this? I think we are all aware that we are probably pretty expendable but nevertheless this is the most crucial time of year for the university with a lot of work needing to be done so I’m guessing training up a whole new section of temps would not be particularly desirable for them. I’m also aware that again the fact that the fifth temp didn’t sign our email is an obvious weakness.
Any suggestions would be much appreciated!

This is a good question, thanks for posting it!
I was in a similar situation once, working in the LSE library. We weren't agency workers, but were casual workers paid hourly by the University. We discussed this amongst ourselves, and decided to go to HR about it. This was after I'd been there a few months, and some of the others had been there over a year. So one of us went to HR and asked about going permanent, and they just gave us all part-time permanent contracts instead. We weren't particularly organised and were quite passive so we ended up actually getting a pay cut based on hourly pay, and an increase of half an hour a week work time. But when holiday pay was taken into account it wasn't so bad, and we all made sure we took some sick days, so we ended up being better off. If we'd been organised though I'm sure we could have stopped the pay cut and time increase.
With your one, I would have approached the employer, i.e. the University rather than the agency. Because it's the University which chooses to pay different rates. Also this would mean you would be less likely to get in trouble with your agency - many agencies forbid you from discussing your wage with other agency workers. Finally, requesting pay rises from an employer benefit the agency as their cut goes up, so it has done the right way they can even be supportive of you.
You collectively approaching your university managers would probably be the best idea. To avoid victimisation it would be good to get the support of permanent workers. They are in a much stronger position since they can't be fired for no reason. Is your department a unionised shop? There must be some UNISON shop stewards around, hopefully that aren't useless. They could even approach management on your behalf - although they may make one or more of you join UNISON before representing you. Alternatively you could just ask any sympathetic co-workers to do so.
To try to avoid having your pay level down, it would be worth finding out what the rate of pay for permanent workers is, and asking to be made level with that (you could even factor in stuff like holiday pay, average sick pay, pension contribution etc). You could use the forthcoming equal pay law for agency workers in your argument, saying that they are going to have to equalise your pay anyway at some point.
In my council I had plans to set up a website for agency workers to post up all their pay rates to try to get them equalised, but now the law is coming in it doesn't seem worth it now.
Good luck though, let us know how it goes!