The ¹⁴C dating of fossil eggshells is often of interest, as these eggshells may occur in Pleistocene or Holocene deposits with diagnostic morphology and/or stratigraphic associations that make them useful in testing hypotheses. This paper discusses methods for ¹⁴C dating of the carbonate fraction of the eggshell. The protein fraction is much smaller, and is likely to be too low for conventional ¹⁴C dating methods. Experimental work is carried out on modern eggs from chickens fed controlled diets. The egg physiology of modern avian species is assumed to be analogous to that of extinct species. The ¹⁴C content of the eggshells produced during this experiment was found to reflect the ¹⁴C activity of feed and atmospheric CO₂ regardless of the amount of ¹⁴C depleted scratch ingested. It is concluded that ¹⁴C dates on eggshell carbonate should reflect the date of organic nutrients the birds consumed, and require little or no correction. The same post-depositional effects previously reported for marine shell carbonate apply to eggshell carbonate, thus the same laboratory pretreatment procedures should apply. The ^13C/12C ratio is not found to reflect the diet completely, and may be affected by kinetic or equilibrium processes at the lung membrane. -- AATA