Assuming the pension is a "qualified" plan, see this chart.
https://www.irs.gov/pub/irs-tege/rollover_chart.pdf
You can roll it over to almost any other type of retirement account. Of course, if you rollover a pre-tax plan to a Roth account, that is a taxable conversion. If you don't want to pay tax, you will roll it over to another pre-tax account. To avoid problems with withholding, do a direct transfer between the 2 plans rather than having the pension send you a check that you forward to the new plan.
