Varshi Tap (Varshitap) has a traditional fixed start and end based on the Jain lunar calendar.

1. General rule (every year) According to Jain tradition, Varshi Tap is usually started on:

• Chaitra Shukla Ashtami (8th day of the bright half of Chaitra)

and ends on

• Vaishakh Shukla Tritiya (Akshaya Tritiya) of the next year, with parna (breaking the fast).

So:

• You formally “start Varshi Tap” on Chaitra Shukla 8.
• You do alternate‑day fasting till next year’s Vaishakh Shukla 3 (Akshay Tritiya).

You can read more here

2. For the year 2026 (if you are asking about current cycle) For 2026, JainKnowledge specifically notes:

• Parna (ending) of Varshitap will be on Monday, 20 April 2026 (Vaishakh Shukla 3 – Akshaya Tritiya).
• That means the Varshi Tap that ends in 2026 would have started on Chaitra Shukla 8 of 2025.

Details here

3. If you personally want to start now If you are asking, “From which tithi should I begin?” then:

• Traditionally: Start on Chaitra Shukla Ashtami of the coming year and take a proper niyama (vow) in front of Jinendra Bhagwan and your guru / vidhikar.
• Do not start such a big tap casually on any random date without guidance.

Practical steps before starting Varshi Tap

1. Consult your Jain guru / knowledgeable vidhikar

- To confirm: - Exact start tithi according to your sampraday (Śvetāmbara / Digambar) and local panchang. - Whether your body and health are suitable.

1. Prepare gradually

- Start with upvās, ayambil, attham, masakshaman etc. - Learn rules of boiled water, samayik, pratikraman, brahmacharya (celibacy), ahimsa during tap.

1. Take formal vow (niyama)

- In front of Jin idols and guru, with - Navkar mantra - Sankalp for: alternate‑day upvās till Akshaya Tritiya

For a simple English explanation of Varshi Tap vidhi, see here

In short:

• Traditional start = Chaitra Shukla 8.
• Traditional end = Next year Vaishakh Shukla 3 (Akshaya Tritiya) with parna.
• Always begin only after taking guidance and permission from your guru.