Ekasana (ekashna) means eating one meal in one sitting, during daylight, before sunset. Pachchakkhan is the vow you take before starting that single meal. If you eat after you have taken the ekasana pachchakkhan, the vow for that day has been broken and the ekasana for that day would not be considered completed.

Key points:

• The pachchakkhan is valid only if you then eat one meal in one sitting before sunset.
• If you forget or eat before finishing the plan, you should not count that day as observing ekasana; you may re‑take pachchakkhan before the next planned meal and observe it properly that day.
• In general, you observe ekasana from sunrise/sunrise window to before sunset; eating after sunset or after breaking the vow would shift the schedule to the next day.

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