My husband and I are both USPS letter carriers. Should we elect survivor benefits?

Unfortunately I cannot answer this question for you. This is a decision you and your spouse have to make. A few things to consider. First, there is a law that says a full survivor benefit must be elected unless the spouse is willing to sign and notarize a form accepting a partial benefit or none at all. It does not make any difference if you are both federal employees. Second, when the cost of the survivor benefit is elected, the cost is calculated and it does not go up. The cost is taken prior to the taxing of your pension. Third, if your spouse dies first (or in your case you die first) a copy of the death certificate should be mailed the OPM and the survivor benefit cost is added back in, the month following the date of the death of the spouse. So then one receives a full pension plus a survivor benefit from the deceased spouse. And finally, a consideration is if you or your spouse dies, can the one surviving live on just their pension alone? I hope this helps in making your decision.