Fines for overstay

esecholito wrote:

We may go a few days over th 180 days mexico gives onthe fmm, does anyone know what fines are applied if we go over a week or two or even a month? Is it calculated daily? Monthly or just one fixed fine?

It is calculated monthly, as far as I know.

" Official fines for failure to surrender an FMM are reported at roughly $1150 - $1,500 MXN (Pesos) for the first month. Subsequent months have been quoted at $600 MXN a month." This was in 2012.

Another option is to not break the law, becoming an illegal alien. Go home when you said you would.

Where are you?  If you're anywhere near a border or near an INM office, ask.  Or rather tell them your story.
If near a border, any border, you should be able to turn the old one in and get another.

I should mention that if you can walk across a border you're not likely to be challenged.  If you can do it before the FMM expires, it should be no problem turning around and getting a new one right at the border.

This link hints at being able to get a new FMM at any INM office.  If you still have some time before the FMM expires, it doesn't hurt to ask.
http://www.bajabound.com/before/permits/visa.php