Good question — increasing average order value (AOV) is one of the fastest ways to grow revenue without increasing traffic. Below is a compact, prioritized playbook you can implement on Shopify with concrete actions, copy examples, and measurement steps.

1. Quick definitions + how to measure

• AOV = Total revenue / Number of orders (over the same period).
• Track in Shopify Analytics (Dashboard > Analytics) and in whatever analytics you use (GA4, etc.).
• Useful related metrics: attach rate (how often customers buy the add-on), conversion rate, and revenue per visitor (RPV).

2. High-impact strategies (with how-to notes for Shopify)

• Free-shipping threshold

  • Offer free shipping at a target order value (e.g., current AOV is $40 → set free shipping at $60–$80). People add to cart to unlock free shipping.
  • How to set: Shopify admin > Settings > Shipping and delivery (create shipping rate based on order price) or use shipping profiles/apps for complex rules.
  • Tip: Display a progress bar on site header/cart showing “$X away from free shipping.”

• Product bundles and kits

  • Bundle complementary items into a slightly discounted package (e.g., 2 for 10% off).
  • How to set: create a bundle product or use a bundle app (or use a single SKU for kits). Make savings obvious on the product page.
  • Tip: Show per-item savings and compare to buying separately.

• Upsells and cross-sells on product pages and cart

  • Product page: “Frequently bought together”, “Customers also bought”, or recommended add-ons (accessories, warranty).
  • Cart drawer/cart page: show 1–2 high-margin add-ons with clear one-click add.
  • How to set: enable Shopify’s product recommendations and/or install an upsell/cross-sell app/widget.

• Post-purchase one-click offers

  • Offer a one-time discounted add-on immediately after checkout (no re-entering card).
  • How to set: use a post-purchase upsell tool or the checkout extensibility features if available for your plan (Shopify Plus has script capabilities).
  • Tip: Keep offer simple and time-limited; conversion rates are often high.

• Tiered discounts / volume pricing

  • “Buy 2, get 10% off; buy 3, get 15% off” — encourages larger multiplies.
  • How to set: Shopify admin > Discounts (create automatic discounts or discount codes) or use an app for dynamic tiered pricing.

• Bundled shipping/savings messaging at checkout

  • Reinforce savings in the cart and checkout: “Add $X more and get free shipping” and show bundle savings.
  • How to set: customize cart template or use cart messaging apps/snippets.

• Subscriptions & replenishment

  • Convert one-time buyers into subscription customers and offer a discount for the first few cycles.
  • How to set: add a subscription option for eligible products via a subscription app/integration.

• Loyalty / points programs

  • Reward spending with points that can be redeemed once a threshold is reached — incentivizes larger carts to earn rewards faster.
  • How to set: install a loyalty/points app and promote the benefit on product pages and at checkout.

• Limited-time bundles and scarcity

  • Flash bundle deals or limited-stock combos can drive urgency to add more items now.
  • How to set: create limited-time collections and promote via banners, email, and on-site timers.

3. Conversion & pricing psychology tips

• Show savings in absolute dollars, not just percentages (“Save $12” converts better than “10% off”).
• Use anchor pricing: show original price struck-through plus bundle price.
• Use social proof on bundles (“X customers bought this combo last week”).
• Offer low-cost impulse add-ons (under $10) with high margins.

4. UX & copy examples you can add quickly

• Cart progress bar: “You’re $22 away from free shipping — add one more item to save!”
• Product page upsell block: “Add matching charger for $9.99 (save $5).”
• Post-purchase offer: “Special one-time offer: 50% off our travel case — accept now, no extra checkout.”

5. Measurement & testing

• Benchmarks: track AOV, attach rate (add-on units / orders), conversion rate, and RPV before/after each change.
• A/B tests: test one change at a time (free shipping threshold vs. progress bar; bundle sales vs. single item).
• Sample test cadence: run each A/B test for at least two weeks or until statistically significant (or based on your traffic volume).

6. Quick wins (implement in 1–2 days)

• Add a free-shipping threshold + site-wide banner/progress indicator.
• Add one product recommendation/“frequently bought together” widget to product pages.
• Create 2 simple bundles (best-seller + accessory) and promote on homepage.

7. Medium-term (2–8 weeks)

• Implement cart upsell and post-purchase one-click offer.
• Launch tiered discounts and at least one subscription option.
• Start a basic loyalty program.

8. Longer term (2–3 months)

• Optimize bundles by margin and conversion.
• Roll out personalization (recommendations based on browsing/purchase history).
• Run regular A/B tests and iterate.

9. Where to invest (priority)

• Highest ROI: free-shipping threshold + cart progress UI, product recommendations, post-purchase offers.
• Good next: bundles/kits, tiered discounts, subscription options.
• Ongoing: loyalty, personalization, creative promotions.

10. Example KPI targets (adjust to your business)

• Increase AOV by 15–30% within 90 days by combining free shipping threshold + bundles + one post-purchase offer.
• Target attach rate for add-ons: 10–25% (varies by product).
• RPV should grow proportionally with AOV if conversion rate stays steady.

If you want, I can:

• Build a 30/60/90-day plan tailored to your current AOV, product prices, and margins.
• Draft on-site copy, banner text, and an A/B test matrix for your store.

Tell me your current AOV, average product price, and top-selling products if you want a tailored plan.