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v1South Dakota
Not yet verified by an accountantContact accountant
1---
2name: sd-sales-tax
3description: Use this skill whenever asked about South Dakota sales tax, South Dakota use tax, South Dakota DOR filing, South Dakota Wayfair, South Dakota municipal gross receipts tax, or South Dakota sales tax compliance. Trigger on phrases like "South Dakota sales tax", "SD sales tax", "SDCL §10-45", "South Dakota DOR", "Wayfair", "South Dakota grocery tax", "South Dakota SST", "South Dakota no income tax", or any request involving South Dakota sales and use tax compliance. ALWAYS load us-sales-tax first for federal context.
4jurisdiction: US-SD
5validation_status: ai-drafted-q3
6---
7 
8# South Dakota Sales and Use Tax Skill
9 
10---
11 
12## Skill Metadata
13| Field | Value |
14|-------|-------|
15| Jurisdiction | South Dakota, United States |
16| Jurisdiction Code | US-SD |
17| Tax Type | Sales and Use Tax (state + local) |
18| State Rate | 4.50% |
19| Municipal Tax | Up to 2.00% |
20| Municipal Gross Receipts Tax | Additional (varies by municipality) |
21| Maximum Combined Rate | ~6.50% + municipal gross receipts |
22| Primary Statute | South Dakota Codified Laws (SDCL) §10-45 |
23| Governing Agency | South Dakota Department of Revenue (DOR) |
24| Portal | https://dor.sd.gov |
25| SST Member | Yes -- Full Member |
26| No State Income Tax | Yes |
27| Contributor | Open Accounting Skills Registry |
28| Validated By | Pending -- requires US CPA or EA sign-off |
29| Validation Date | Pending |
30| Skill Version | 1.0 |
31| Confidence Coverage | T1: state rate, basic taxability, filing mechanics, Wayfair background. T2: municipal gross receipts, service taxability, exemption specifics. T3: audit defense, complex transactions, penalty abatement. |
32| Format | Restructured to Q1 execution format, April 2026 |
33 
34---
35 
36## Confidence Tier Definitions
37- **[T1] Tier 1 -- Deterministic.** Apply exactly as written. No reviewer judgement required.
38- **[T2] Tier 2 -- Reviewer Judgement Required.** Claude flags the issue and presents options. A licensed CPA, EA, or tax attorney must confirm before filing.
39- **[T3] Tier 3 -- Out of Scope / Escalate.** Do not guess. Escalate to a licensed tax professional.
40 
41---
42 
43## Step 0: Client Onboarding Questions
44 
45Before proceeding with any South Dakota sales tax analysis, collect the following from the client: [T1]
46 
47| # | Question | Why It Matters |
48|---|----------|---------------|
49| 1 | Do you have a South Dakota sales tax registration / tax ID? | Determines whether registration is needed before filing. |
50| 2 | What is your current filing frequency (monthly / quarterly / annually)? | Controls which return periods to prepare. |
51| 3 | What is your nexus type -- physical presence, economic nexus, or both? | Determines registration obligations and applicable rules. |
52| 4 | Are you a marketplace seller (selling through Amazon, Etsy, etc.)? | Marketplace facilitator may already be collecting on your behalf. |
53| 5 | What types of products or services do you sell in South Dakota? | Drives taxability classification under South Dakota law. |
54| 6 | Do you sell to exempt entities (government, nonprofits, resellers)? | Determines whether exemption certificates must be collected and retained. |
55| 7 | Do you have locations, employees, or inventory in South Dakota? | Physical presence creates nexus independent of economic thresholds. |
56| 8 | Do you sell into multiple South Dakota local jurisdictions? | Local tax rates vary; determines compliance complexity. |
57 
58**If the client cannot answer questions 1-4, STOP and gather this information before proceeding.** [T1]
59 
60---
61 
62## Step 1: Tax Rate Structure
63### 1.1 State Sales Tax Rate
64 
65South Dakota imposes a state sales tax of **4.50%** on the gross receipts of all retail sales of tangible personal property and services. [T1]
66 
67**Statute:** SDCL §10-45-2.
68 
69### 1.2 The Wayfair State [T1]
70 
71South Dakota is historically significant as the state whose law was upheld in **South Dakota v. Wayfair, Inc., 585 U.S. ___ (2018)**, the landmark US Supreme Court decision that overruled Quill and established that states may impose sales tax collection obligations on remote sellers without physical presence. [T1]
72 
73This case revolutionized US sales tax by enabling economic nexus nationwide. [T1]
74 
75### 1.3 No State Income Tax [T1]
76 
77South Dakota has **no state individual or corporate income tax**. Sales tax is the state's primary revenue source. [T1]
78 
79### 1.4 Local Sales Taxes [T1]
80 
81- Municipalities may impose a local sales tax of up to **2.00%**. [T1]
82- Combined state + municipal rates can reach approximately **6.50%**. [T1]
83- **Municipal gross receipts tax:** Some municipalities impose an additional gross receipts tax on specific industries (restaurants, hotels, bars), typically 1-2%. This is IN ADDITION to the sales tax. [T2]
84 
85### 1.5 Very Broad Tax Base [T1]
86 
87South Dakota has one of the broadest sales tax bases in the country:
88- Virtually ALL services are taxable. [T1]
89- ALL food (including groceries) is taxable. [T1]
90- This broad base allows the state to maintain a relatively low rate. [T1]
91 
92### 1.6 Sourcing [T1]
93 
94South Dakota uses **destination-based** sourcing. [T1]
95 
96As an SST member, South Dakota follows SSUTA sourcing rules. [T1]
97 
98---
99 
100## Step 2: Transaction Classification Rules
101### 2.1 Grocery Food -- TAXABLE at Full Rate [T1]
102 
103**South Dakota taxes grocery food at the FULL 4.5% state rate + local.** [T1]
104 
105- Unprepared food: taxable at 4.5% + local. [T1]
106- Prepared food: taxable at the same rate. [T1]
107- There is NO reduced rate or exemption for food. [T1]
108- South Dakota is one of the few remaining states that fully taxes grocery food. [T1]
109 
110### 2.2 Clothing [T1]
111 
112- Clothing is **fully taxable**. No exemption. [T1]
113 
114### 2.3 Prescription Drugs and Medical [T1]
115 
116- Prescription drugs: **exempt**. SDCL §10-45-14.5. [T1]
117- OTC drugs: **taxable**. [T1]
118- DME: exempt with prescription. [T1]
119- Prosthetics: exempt. [T1]
120 
121### 2.4 Services -- VERY BROADLY TAXABLE [T1]
122 
123**South Dakota taxes virtually ALL services.** Along with Hawaii, New Mexico, and West Virginia, South Dakota has one of the broadest service tax bases. [T1]
124 
125Taxable services include (non-exhaustive):
126- Professional services: legal, accounting, consulting, engineering, architecture. [T1]
127- Personal care: haircuts, spa services. [T1]
128- Repair and maintenance. [T1]
129- Cleaning and janitorial. [T1]
130- IT services, web design, software development. [T1]
131- Construction services (labor + materials). [T1]
132- Marketing and advertising. [T1]
133- Financial advisory services. [T2]
134- Telecommunications. [T1]
135 
136**Very limited exemptions from services:**
137- Medical services (physicians, dentists, hospitals). [T1]
138- Insurance premiums (subject to premium tax instead). [T1]
139- Banking/financial institution services (some). [T2]
140 
141### 2.5 SaaS and Digital Goods [T1]
142 
143- **SaaS:** **Taxable**. South Dakota taxes all electronically transferred products and services, including SaaS. SDCL §10-45-4.2. [T1]
144- **Digital downloads:** Taxable. [T1]
145- **Streaming services:** Taxable. [T1]
146- **Canned and custom software:** Taxable. [T1]
147 
148### 2.6 Manufacturing [T2]
149 
150- Manufacturing equipment: no specific broad manufacturing exemption in South Dakota. [T2]
151- Raw materials incorporated into finished products for resale: exempt under resale. [T1]
152- South Dakota's broad base means most equipment purchases are taxable. [T1]
153 
154### 2.7 Agricultural [T1]
155 
156- Farm machinery and equipment: **exempt**. SDCL §10-45-14. [T1]
157- Feed, seed, fertilizer: exempt. [T1]
158- Livestock: exempt for breeding/production. [T1]
159- Agricultural chemicals: exempt. [T1]
160 
161---
162 
163## Step 3: Return Form Structure
164### 4.1 Filing Details [T1]
165 
166| Field | Detail |
167|-------|--------|
168| Return Form | South Dakota Sales Tax Return (filed via DOR portal) |
169| Filing Frequencies | Monthly (>$250/month avg); Quarterly ($50-$250); Annually (<$50) |
170| Due Date | 20th of the month following the reporting period |
171| Portal | https://dor.sd.gov |
172| E-filing | Required for most filers |
173 
174### 4.2 Vendor Discount [T1]
175 
176South Dakota does NOT offer a vendor discount for timely filing. [T1]
177 
178### 4.3 Penalties and Interest [T1]
179 
180- Late filing penalty: 10% of tax due or $10, whichever is greater. [T1]
181- Interest: 1% per month (12% per annum). [T1]
182- Fraud penalty: 100% of tax due. [T1]
183 
184---
185 
186## Step 4: Deductibility / Exemptions
187Exemptions identified in Step 2 above are the primary deductibility rules for South Dakota. Key categories: [T1]
188 
189- **Resale exemption:** Valid resale certificate required. Retain for the statutory period. [T1]
190- **Exempt organizations:** Government entities and qualifying nonprofits -- require exemption certificate on file. [T1]
191- **Agricultural exemptions:** Where applicable per Step 2. [T1]
192- **Manufacturing exemptions:** Where applicable per Step 2. [T2]
193 
194All exemption certificates must be collected at or before the time of sale and retained per the state's statute of limitations. [T1]
195 
196 
197---
198 
199## Step 5: Key Thresholds
200### 3.1 Economic Nexus Threshold [T1]
201 
202| Field | Detail |
203|-------|--------|
204| Revenue Threshold | $100,000 in South Dakota sales |
205| Transaction Threshold | 200 transactions |
206| Test | OR (either threshold triggers nexus) |
207| Measurement Period | Current or prior calendar year |
208| Effective Date | November 1, 2018 (post-Wayfair) |
209 
210**Statute:** SDCL §10-64-2.
211 
212### 3.2 Marketplace Facilitator [T1]
213 
214South Dakota requires marketplace facilitators to collect and remit. SDCL §10-45-98. [T1]
215 
216### 3.3 SST Registration [T1]
217 
218Full SST member. SSTRS and CSPs available. [T1]
219 
220---
221 
222## Step 6: Filing Deadlines and Penalties
223 
224Refer to Step 3 for filing frequencies and due dates. [T1]
225 
226---
227 
228## PROHIBITIONS
229- NEVER assume grocery food is exempt in South Dakota. It is taxable at the FULL rate. [T1]
230- NEVER assume services are exempt in South Dakota. Virtually ALL services are taxable, including professional services. [T1]
231- NEVER assume SaaS is exempt. South Dakota taxes SaaS and all digital products. [T1]
232- NEVER confuse sales tax with the separate municipal gross receipts tax. They are different obligations. [T2]
233- NEVER forget South Dakota's role as the Wayfair state when advising on economic nexus. [T1]
234- NEVER assume a uniform rate. Municipal taxes vary by city. [T1]
235- NEVER compute any number -- all arithmetic is handled by the deterministic engine, not Claude. [T1]
236 
237---
238 
239## Edge Case Registry
240 
241### EC1 -- Grocery Food Fully Taxable [T2]
242 
243**Situation:** A multi-state retailer assumes food is exempt in South Dakota based on other states.
244 
245**Resolution:**
246- South Dakota taxes ALL grocery food at the full 4.5% state rate + local. [T1]
247- POS systems must be configured to charge sales tax on food. [T1]
248- South Dakota, Alabama, and Mississippi remain among the few states taxing food at the full rate. [T1]
249- **Flag for reviewer:** Verify POS food classification. Common error is configuring food as exempt. [T2]
250 
251### EC2 -- Professional Services Taxable [T2]
252 
253**Situation:** A mainland law firm provides services to a South Dakota client. Is the legal fee subject to SD sales tax?
254 
255**Resolution:**
256- Legal services ARE taxable in South Dakota. [T1]
257- If the law firm has economic nexus in SD ($100K+ or 200+ transactions), it must collect SD sales tax on fees for services delivered to SD clients. [T1]
258- Most mainland professionals are unaware that SD taxes professional services. [T2]
259- **Flag for reviewer:** Service providers from states that exempt professional services often fail to collect SD tax. Verify compliance. [T2]
260 
261### EC3 -- Municipal Gross Receipts Tax [T2]
262 
263**Situation:** A restaurant in Sioux Falls owes both sales tax and municipal gross receipts tax. How do they interact?
264 
265**Resolution:**
266- The restaurant collects and remits 4.5% state + 2% city = 6.5% sales tax. [T1]
267- The municipal gross receipts tax is an ADDITIONAL tax imposed on the restaurant's gross receipts (typically 1-2%). [T2]
268- This tax is on the BUSINESS, not passed to the customer (though businesses often build it into prices). [T2]
269- The two taxes are separate returns/obligations. [T2]
270- **Flag for reviewer:** Municipal gross receipts taxes are filed separately from sales tax. Verify all applicable municipal taxes. [T2]
271 
272### EC4 -- Wayfair Compliance for Remote Sellers [T1]
273 
274**Situation:** A remote seller wants to understand their SD obligation given the Wayfair decision.
275 
276**Resolution:**
277- South Dakota's law (upheld in Wayfair) requires remote sellers meeting the $100K OR 200 transaction threshold to collect SD sales tax. [T1]
278- The law was found constitutional because it: (a) has a safe harbor for small sellers, (b) does not apply retroactively, (c) South Dakota is an SST member (simplifying compliance). [T1]
279- Remote sellers should register through SSTRS for free compliance tools. [T1]
280- **Flag for reviewer:** Wayfair is the foundation of all US economic nexus laws. South Dakota's law is the model. [T1]
281 
282---
283 
284### EC5 -- Consulting Firm from Non-Service-Tax State [T2]
285 
286**Situation:** A management consulting firm from Colorado (where consulting is exempt from sales tax) provides strategic consulting to an SD client. The firm has economic nexus in SD.
287 
288**Resolution:**
289- Consulting services ARE taxable in South Dakota. [T1]
290- The firm must register for SD sales tax and collect on fees for services delivered to SD clients. [T1]
291- The firm's home state treatment (exempt in CO) is irrelevant. Destination state rules apply. [T1]
292- **Flag for reviewer:** Service firms from states that exempt professional services are high-risk for SD non-compliance. [T2]
293 
294### EC6 -- Construction Services [T2]
295 
296**Situation:** A contractor builds a commercial building in Rapid City. The total contract is $1 million (materials + labor).
297 
298**Resolution:**
299- In South Dakota, construction services are subject to sales tax on the ENTIRE contract (materials + labor). [T1]
300- This is different from most states where the contractor pays tax on materials only. [T1]
301- Tax = $1,000,000 x combined rate (4.5% state + 2% city = 6.5%). [T1]
302- The contractor collects tax from the property owner. [T1]
303- **Flag for reviewer:** Contractors from other states may be unfamiliar with SD's treatment of construction as a fully taxable service. [T2]
304 
305### EC7 -- Use Tax on Personal Purchases [T1]
306 
307**Situation:** An SD resident purchases a $2,000 laptop online from a seller that did not collect SD tax.
308 
309**Resolution:**
310- Use tax is due at the same rate as sales tax. [T1]
311- The resident should self-assess use tax on their SD income tax return (SD has no income tax, so use tax must be reported separately). [T1]
312- SD use tax return (SDCL §10-46) is available. [T1]
313- **Flag for reviewer:** In a no-income-tax state, there is no income tax return to add use tax to. Separate use tax reporting is required. [T2]
314 
315---
316 
317## Test Suite
318 
319### Test 1 -- Basic Taxable Sale
320 
321**Input:** Seller in Sioux Falls sells $500 of office supplies. Combined rate = 6.5% (4.5% state + 2% city).
322**Expected output:** Tax = $500 x 6.5% = $32.50. Total = $532.50.
323 
324### Test 2 -- Grocery Food at Full Rate
325 
326**Input:** Customer buys $200 of unprepared groceries in Rapid City. Combined rate = 6.5%.
327**Expected output:** Food IS taxable. Tax = $200 x 6.5% = $13.00. Total = $213.00.
328 
329### Test 3 -- Legal Services Taxable
330 
331**Input:** Attorney in Pierre bills $3,000 for legal services. State rate = 4.5% (no city tax in this example).
332**Expected output:** Legal services ARE taxable. Tax = $3,000 x 4.5% = $135.00. Total = $3,135.00.
333 
334### Test 4 -- SaaS Taxable
335 
336**Input:** SaaS company charges SD business $500/month. Combined rate = 6.5%.
337**Expected output:** SaaS IS taxable. Tax = $500 x 6.5% = $32.50. Total = $532.50.
338 
339### Test 5 -- Economic Nexus (Wayfair Threshold)
340 
341**Input:** Remote seller from Delaware sold $110,000 to SD in the prior year, with 150 transactions.
342**Expected output:** Revenue ($110,000) exceeds $100,000 threshold. Nexus IS triggered (OR test -- revenue alone sufficient). Must register and collect.
343 
344---
345 
346### Test 6 -- Consulting Services Taxable
347 
348**Input:** Consulting firm charges $10,000 for services to an SD business in Sioux Falls. Combined rate = 6.5%.
349**Expected output:** Consulting IS taxable. Tax = $10,000 x 6.5% = $650.00. Total = $10,650.00.
350 
351### Test 7 -- Construction Contract
352 
353**Input:** Contractor charges $500,000 for building project in Rapid City. Combined rate = 6.5%.
354**Expected output:** Entire contract is taxable. Tax = $500,000 x 6.5% = $32,500.00. Total = $532,500.00.
355 
356### Test 8 -- Farm Equipment Exempt
357 
358**Input:** Farmer buys $80,000 tractor for agricultural use.
359**Expected output:** Farm machinery is exempt. Tax = $0. Total = $80,000.
360 
361---
362 
363## Reviewer Escalation Protocol
364 
365| Trigger | Action |
366|---------|--------|
367| Any [T3] tagged item encountered | STOP. Do not guess. Escalate to licensed CPA, EA, or tax attorney. |
368| Client has audit notice or assessment | Escalate immediately. Do not advise on audit response. |
369| Multi-state nexus question involving 3+ states | Flag for senior reviewer with multi-state experience. |
370| Penalty abatement or voluntary disclosure | Escalate to licensed professional with state-specific experience. |
371| Ambiguous taxability of a product/service | Present both interpretations to reviewer with supporting authority. |
372 
373---
374 
375## Contribution Notes
376 
377- This skill follows the Q1 execution format (Step 0 through Step 7).
378- All rules are tagged [T1], [T2], or [T3] per the Confidence Tier Definitions.
379- Rate tables are deterministic lookup tables -- no narrative explanation of rates.
380- To update this skill, submit a pull request with the specific section, supporting statutory authority, and effective date of the change.
381- All changes require validation by a US CPA or EA before merging.
382 
383---
384 
385## Disclaimer
386This skill and its outputs are provided for informational and computational purposes only and do not constitute tax, legal, or financial advice. Open Accountants and its contributors accept no liability for any errors, omissions, or outcomes arising from the use of this skill. All outputs must be reviewed and signed off by a qualified professional (such as a CPA, EA, tax attorney, or equivalent licensed practitioner in your jurisdiction) before filing or acting upon.
387 
388The most up-to-date, verified version of this skill is maintained at [openaccountants.com](https://openaccountants.com). Log in to access the latest version, request a professional review from a licensed accountant, and track updates as tax law changes.
389 

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Q3: AI-drafted

AI-generated with structure and citations. Not independently verified.

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About

Use this skill whenever asked about South Dakota sales tax, South Dakota use tax, South Dakota DOR filing, South Dakota Wayfair, South Dakota municipal gross receipts tax, or South Dakota sales tax compliance. Trigger on phrases like "South Dakota sales tax", "SD sales tax", "SDCL §10-45", "South Dakota DOR", "Wayfair", "South Dakota grocery tax", "South Dakota SST", "South Dakota no income tax", or any request involving South Dakota sales and use tax compliance. ALWAYS load us-sales-tax first for federal context.

US-SDty-2025

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